The reverse levels challenge thread

[Minim]

Looks like the reverse levels idea is popular, so without further ado, I will start this challenge thread.
If you haven't got the reverse level pack don't worry. You can log in (or register) and download the packs here and here.

So here are the following questions:

1. How many levels can be solved in reverse?
2. If the level is impossible with the provided skill set, how many more skills would be required to make the level work?

I have set up a table based on the original set, the pack which I have worked on reversing first. Here's how the table will work:

1. If the level is possible, a 0 is added, implying that there are no additional skills required to solve it.
2. If a different number is shown, it shows how many more skills you would need to make the impossible level possible (for example if Fun 4 required a builder and a basher, then I would put a number 2 on the cell meaning that 2 additional skills are needed before the level can be solved.)
3. An asterisk means that the level is not possible at all, even if you have 99 of each skill, and a reason would be stated.

I hope I explained every part clearly. Enjoy the challenges!

 --------------------------------------------------------------------------------------------------
|Rating | 1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 |
|-------|------------------------------------------------------------------------------------------|
|Fun    | 3  4  8  2  0  3  0  0  0  0  0  0 10  0  0  0  0  5  0  0  0  0  0  0  0  0  0  0  0  0 |
|Tricky | 0 10  0  0  0  0  0  0  0  0  0  0  0  0  3  1  5  4  0  0  0  0  1  0  0  0  0  0  0  0 |
|Taxing | 0  0  0  0  0  2  0  1  4  0  0  0  0  0  0  0  0  0 10  0  0  0  0  0  0  0  0  0  0 10 |
|Mayhem | 0  0  *  3  0  0  0  0  0  0 10  0  0  0  0  5  0  0  0  1  0  0  0 13  0  0  4  0 16  0 |
|-------|------------------------------------------------------------------------------------------|
|Tame   | 0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0                               |
|Crazy  | 0  5  9  3  0  2  0  0  0  0  0  2 11  0  7  0  9  3  0  0                               |
|Wild   | 3  0  0  0  1  0  2  3  0  0  0  0  6  0  6  1  0  0  0  4                               |
|Wicked | 0  8  0  0  1  0 11  0  0  0  0  3  0  8  0  5  3  0  1  1                               |
|Havoc  | 0  1  3  0  2  0  0  0  2  0  0  0  0  0  0  0  5  0  0  7                               |
|-------|------------------------------------------------------------------------------------------|
|Frost  | 0  2  0 12  0 13  0  0  4  1  0  2  0  0  3  2                                           |
|Hail   | 0  0  0  0  0  7  0  0  0  0  0  3  2  0  0  9                                           |
|Flurry | 0  0  0  0  0  0  0 16  0  0  0  0  3  0  0  0                                           |
|Blitz  | 0  1  7  3  0  0  0  6  0  0 13  7  5  1  0 12                                           |
 --------------------------------------------------------------------------------------------------


*Time is too limited for this this level to be solvable.

With the default skillset our final results are:
+ 94 levels are possible in Original Lemmings. (78.3%)
+ 68 in Oh No More Lemmings (68%)
+ 41 in Holiday lemmings '94 and '93. (64.1%)

While many levels are possible with additional skills, only one level is confirmed impossible. If the time wasn't an issue, then this only level would be solvable with 8 additional skills. Well done everyone!

[Clam]

Here's Fun 18 with 5 added skills, 4 builders and 1 basher.

Also, Fun 5 can be done with the default skillset, as I posted here (now with replay )

[finlay]

Tricky 4 is definitely possible...

Also I completed Mayhem 18, 19 and 28. (posted a replay of 19 in the other thread because I'm quite proud of working out the tricky bomber timing )

And Tricky 24 (Tightrope City) is possible too. It should be doable at 100% with the same release-the-blocker-and-turn-him-around trick that you used for Fun 9, but I'm not very good at pulling that off. (basically, you do a two blocker trap with one directly underneath the entrance, and then once you've used 1 builder to go over the gap, you can release the blocker under the entrance, and then you can probably release the other one too or something, I dunno, it's easy to solve, anyway!)

And here's Tricky 25, which is non-trivial and therefore quite fun. I saved 70/80, which is a lot more than the "normal" solution going forwards, but I don't think you can save 100%...

Taxing 13 is also possible (replay on request) – I ended up saving the minimum 98%, though, because I couldn't be bothered working out how to release my blocker (I had run out of bashers, so I tried with a miner which didn't work, but maybe if I put the blocker higher up on a stalk it might that way)

I suspect Taxing 14 is probably possible, given that it's not a particularly hard builder level to begin with. I'm not sure I can be bothered trying it, though.

Taxing 16 is also possible (again, replay on request) – I did it for 97% and finished with literally no time to spare, though, because building up to the exit takes a bit of time and there is only 3 minutes on the clock (the original level had a bit of this but not to the same degree). That said, I could have comfortably exploded the blocker a wee bit before I actually did, so it's my fault really for making the timing so tight.

Taxing 22 is possible, although I don't know about 100%.
Taxing 23 is possible – same solution as the tricky level.
Taxing 24 is possible and not hugely difficult – I think there are a couple of possible ways of doing it.
Taxing 26 is possible. It might be mildly more difficult to get to the top exit, though. I haven't tried yet.
Taxing 27 is possible (just have to bomb down).
Taxing 28 is possible. I haven't ascertained whether it's possible on 100%, but I had a few skills left over, so it may well be (unlike the forwards level of course!)
Taxing 29 is possible. It's not as trivial as some of the others, though, as you have to build up to the mound on the left using the 5 builders, and then you need to climb up the last little bit in order to block and release. I've managed lose 2, and there's a replay if you want.

Taxing 30 is definitely impossible with the current skill set – I think all the We all fall downs will have the same extra skillset needed, but I'm not sure what that might be.

Mayhem 1 is possible. I dunno about 100% though, I did it with blockers for lose 2. There's an awkward bit when you're going down where you need a floater, and you could probably use an extra blocker and lose 1 more to make it less tedious, but I (having found Lemmix's skip-ten-seconds function, which makes building much less tedious!) built over to the exit and back again to make the drop safe.
Mayhem 2 is also possible, and again, the fact that the level has floaters comes in handy.

Mayhem 3 is definitely impossible with the current skillset. Given the time limit, I'm not sure if it will be possible with any skillset, to be honest. (With the Fun 24 skillset, I had to build to get up to the exit, which took quite a long time.)
Mayhem 4 is impossible, but can be made possible with 3 builders and 2 blockers. (same way I did Fun 25)

I'm pretty sure Mayhem 5 is impossible with only 5 builders, but feel free to prove me wrong here!

Mayhem 6 is possible, and fairly easy (just build through the gap).

Mayhem 7 seems to be impossible. I think there is a possible solution if you add a digger and a miner (I trapped the lemmings to the right of the entrance by digging down – this way a climber can get up, and later in the level you can dig+mine down to release the lemmings). However, there may be something I'm overlooking here. I'm not sure I know the "best" solution to the forwards level.

Mayhem 8 is possible, and not too hard.
Mayhem 9 is possible too. Not sure about 100%, I used the blocker. Should be possible though, because you can probably make a digger trap and there are plenty of skills left over.
Mayhem 10 is possible. It's quite fun as a multitasking level, too, and getting down from the Pillars is quite interesting, so it's a bit harder than the original overall. I managed a lose-4 solution – although I'm sure that's not the maximum, I'm not sure about 100% because I needed a blocker for the right entrance. (Also, what the hell is with Lemmix's entrance order? That confused me for a minute there when the lemming didn't come out of the correct trapdoor!)

Mayhem 11 is impossible, as we know.
Mayhem 12 looks impossible to me, or at least too difficult to attempt at 1 in the morning. However, I know that Clam can glitch through the wall, so that might be our best option here, if it's indeed possible.

I don't think Mayhem 13 is possible from a cursory glance over it.

Mayhem 14 is fairly symmetrical, so should be as possible from the right as it is from the left. I haven't attempted it, however.

Mayhem 15 is possible.

Mayhem 16... not even going to attempt it to know it's impossible.

Mayhem 17, again, is very symmetrical, and should be as possible from the right as from the left.

Mayhem 18 & 19 are possible.

Mayhem 20 is impossible; as impossible as Fun 4 was.
Mayhem 21 seems to be impossible from a cursory glance, but I think it might be possible with one extra basher.

And as I mentioned, it's about 1 in the morning here now, so I hope this has been of assistance. I'll let you guys finish the levels off and confirm the ones I'm not sure about.

[ccexplore]

(Also, what the hell is with Lemmix's entrance order? That confused me for a minute there when the lemming didn't come out of the correct trapdoor!)

Believe it or not, this is actually emulation for a bug in PC Lemmings.  The lemmings do come out in ABBA order for 2 entrances in that version.

This bug is fixed for PC ONML onwards (and Lemmix account for that as well), but unfortunately as a side effect, it exposed that (this is well-known) Lemmix is not handling 3-entrance ordering correctly for ONML and Xmas levels (4-entrance ordering is okay).  Although I think we might be okay for reversed levels, as I don't recall off top of my head any levels in ONML or Xmas that have 3 exits.

=========

This does remind me of one thing though:  for the few reversed levels that wound up with multiple entrances, we should canonicalize the entrance ordering.  I would propose that the relative object ordering be left as is.  This is reflected by the "index" property shown in Lemmix and LemEdit.  So if there are 3 exit objects A, B and C with indices 0, 3, 6, the resulting entrances in the reversed level would have A, B, and C in that order, and so the lemmings are released A, B, C, B, ....

This may already be the case in minimac's levels but I have to double check (I intend to do a full pass on them over the next day or so to fix any and all remaining mistakes).

[finlay]

I think that's right: the only level with 3 exits is Fun 23/Taxing 18 (and there are only 4 levels with multiple exits in L1 and ONML anyway).

The simplest way to convert the levels (and I don't know if minimac has done it this way) is presumably to take each individual object and change its object ID number, ie directly change an entrance into an exit or vice versa. (and then change its y-coordinate so that the exit is on the ground and the entrance is above the ground)

I think as long as we're being consistent about using the same level sets it's fine either way, really.

Anyway, I'd be interested in seeing ONML done too (I predict that fewer levels will be possible). I might have a go myself. But another day... seriously, I've got to stop staying up late on the internet! (it's now almost 3)

[Clam]

I looked through the first half of Mayhem, and found some improvements to finlay's (impressive ) late-night efforts:

Mayhem 4 can be done with 3 extra skills (1 blocker, 2 builders), by using the 'spare' bashers to stall some lemmings and prevent them falling off the level. With one less builder, I ended up about 10 lemmings short after using up all the bashers; I'm not seeing much room for improvement here.

Mayhem 5, 7 and 13 are all possible, thanks to some sliding magic.

Mayhem 12 can be done by going through the ceiling, remembering that the top part of the steel is useless at stopping bashers. My 'cursor-digging' solution to the original level depends on some steel cancelling from the exit-top piece (otherwise you can't get far enough through the steel), so that's not possible any more. However, this comes down to how you define 'swap the entrance and exit' - if you swapped the entrance and exit objects and left the top piece where it was, you could get through there, but I think it's sensible to move the exit top to the exit's new location.

As for Mayhem 3, I had a quick run at it and got a lemming to within about 2 seconds of the exit. I used the slow climbing-in-wall glitch instead of sliding, so I'm almost certain you can make up that time, and since there's some building required to get to the top, you have some time to organise the crowd. This is going to be a heck of a mission though, so I propose we leave this one til last

[Minim]

And as I mentioned, it's about 1 in the morning here now, so I hope this has been of assistance. I'll let you guys finish the levels off and confirm the ones I'm not sure about.

OK, I have taken a look at the last nine Mayhem levels, and found the following to be possible:

22 isn't too difficult.
23 is possible and it does involve a nice range of obstacles for you to go through.
24 is already impossible with just three bashers. It may work using the slider trick though, but you need 100% and with a 99 release rate, the problems get worse.
25 and 26 are levels I had no problems with.
28 I have done already, along with finlay, so we both confirmed that it's possible.
30 is so possible, it is FAR too easy for it's position considering there's a choice of exits.

[finlay]

You missed a couple of the alterations I suggested! In particular, Tricky 24 & 25 and Taxing 13 are definitely possible and Taxing 14 should be, but it's just a boring level that I can't be bothered playing through.

Mayhem 14 is also fairly easy (except one of the peas has a permissible landing zone of 4 pixels that just jut above the trigger area, and it's harder to accurately predict either where to start building in order to land there or where to dig in order that both your hero lemming and the crowd land on it); I just completed it now to check, anyway.

EDIT: I converted all the ONML levels. They're in the other thread.

[finlay]

Well, I can confirm for definite that all of the Tame levels are incredibly possible even when reversed. Some of them are now very easy (particularly ones like 13, which now requires no skills, or 20, which only requires one basher), while some are suddenly not difficult, but at least non-trivial, such as 5, 17 and 18. More building is required, of course, except in the levels like 13 and 20 which required it before (yes i know that strictly speaking only 1 builder is required for level 13 and none for 20, but normal-person solutions require 4 for both!)

Crazy 1, 5, 7, 8, 9 are possible.

Crazy 10 is possible because the trigger area for the water trap is slightly below a piece of rock in which the water is embedded. I'm sure it'd be possible to find another way, because there are a few skills left over. I've attached a screenshot.

Crazy 11 is possible, but it turns out that lemmings walk off the right hand edge of the level (while they bounce off the left hand edge of the level cf Crazy 19, Taxing 18), so you need to use a bunch of bridges to turn the lemmings around... I'm not nearly as good at this as the likes of cc, though.

Crazy 13 is possible, and made a lot easier because of direct drop (so it only needs a blocker to turn the lemmings round for instance). This is one of those places where you could make a case for moving the exit slightly, because I don't think that point is where the lemmings would land on the forwards level, but it's where the exit ended up by me not moving the X-coordinate of the object in the editor, so I'm going to keep it like that.

And finally from the Crazy set, Crazy 20 is possible.

I can also confirm Wild 9 & 10 as possible – Wild 10 has a convenient and easy direct drop solution, at least. It should be possible going all the way round too but I can't be bothered confirming that.

Some of the other early Wild levels are impossible ("You take the high road" is particularly frustrating because it looks like it should be possible but seems to require 2 extra builders – you can put that down as its total (Wild 7!)), and the others I just haven't attempted. I haven't attempted any levels later in the game than that.

[Minim]

As promised, I've done some Havoc levels, and I will eventually evaluate on the ones that haven't been done yet:

1 is possible, as long as you know where the hidden trap is...
4 took me a few tries to get it right, but I went underneath the terrain managing to bash two pixels away from ground zero. I managed to re-turn the lemmings back to the right by building on top of the gaps in the ceiling.
6 had me frustrated that it wasn't possible, all because there aren't enough builders for me to take the outside route. It would've been handy having the platform on the right though, as that could've helped the reverse solution.
7 and 8 aren't too difficult
10 is possible, and a lot easier in reverse than normal. I managed to get double the requirement.
11 looks impossible from a casual player's point of view, but if I had more builders, a ceiling route would've been viable.
12 is possible, as long as you place your builders correctly.
13-16 I had no problems, saved a lot of skills
18 is possible, and has a cool solution.
19 even though the lemmings were stuck, I still managed to get them out complete the level easily.

Let the last lemming dig when on the silver platform. Build over the gap. Dig 6 times then bash through the bricks. Build up to the exit. Meanwhile set a blocker next to silver pillar, and blow him up.

I'm amazed that I solved more than half of the Havoc levels.

[finlay]

Oh wow, I've only just noticed now while watching Clam's replays that Mayhem 5 has no flamethrower traps. I thought they'd been accidentally deleted... turns out I just really don't know what was kept and deleted from the DOS version of lemmings...

[Minim]

There are two Taxing levels that I am having trouble with: 8 and 19. On 8, I can't seem to turn the lemmings around even with plenty of skills. You still will need 100% for that. For 19, I can only go as low as 67 additional skills. Using 64 climbers, 1 blocker and 2 builders. I'm pretty sure there's a more efficient way, but as there are only 2 minutes, the climbing seems to be the only method that is viable. The other is the sliding trick, but I can't pull that off.

Edit: I managed to get 19 down to 26 additional skills (Only just in time though). I've found a third method of steep digging down the left wall, combined with building and blowing up the two bars above the entrance.

[DragonsLover]

How Taxing 8 is impossible? If it's the matter of turning the Lemmings around, then you could use Builder + Miner + Steel trick for that, but then, it would require A LOT of additionnal skills to add. And I "think" there's plenty of time.

[finlay]

On 8, here's what you have to do to have all the lemmings walking left. I have attached a demonstration replay, which is not an example of how to complete the level, but the rest should be simple if you want to give it a go. I gave the level 99 builders, blockers and diggers in order to experiment with them (the replay uses about 12 builders, 2 blockers and a digger, but give the level more than that just in case), and found that lemmings start bugging out when they get too close to the top of the screen – they're doing something I personally have never seen them do before, which is transitioning from a walker to a faller or something. There's a possibility that the bug only happens on Lemmix (it rings a bell. but I really don't know that much about the inner workings of Lemmings or Lemmix. it's just a bug I haven't seen before, and I don't have that much experience with DOS lemmings anyway!), but I don't really care about that at the moment. Basically, you keep hammering on the mouse when the builder is near the top of the screen; I think three times he'll stop building before he bugs out on the top of the screen; then if you do it correctly you can release him with a digger, and he'll walk back down the bridge without having damaged it (I couldn't work out the rule for it, but sometimes he dug through the bridge and I'd have to start again). When he or any other lemming walks back up they'll change direction. Then you can release a blocker that you've made on the metal platform.

The other option I considered was bashing through the top of the steel, but unfortunately the steel area is set a few pixels above the top of the steel, so this wasn't an option in the end. I'm not sure the builder+miner+steel trick will work if the steel area is set a few pixels above. (edit: just confirmed, and it doesn't!)

By the way, how did you solve We all fall down in the end? What skills did you add?

More editing: OK, I've solved Taxing 8 with 1 blocker, 1 digger, 23 builders and 9 bashers. Since the original provides no blockers or diggers and only 10 builders, that's a total of 15 extra. [It's possible that the totals of builders could be reduced – some of the builders I used were mainly to slow lemmings down so that they didn't die, though. Another option at the start would be a two blocker-trap – it wouldn't be too difficult to build on the left, block, and then later bash to release him. I've also just realised that I could have saved 3 builders by not building over the gaps in the balls and just bashing through the balls themselves (the way i did it is just how I learnt to solve the level when I was a kid, and old habits die hard!) 15 will do for now though!]

Even more editing: because you missed it before, Wild 7 should be 2 extra builders. I'm also not convinced that Havoc 17 is completely impossible – sure, those pesky traps are annoying, but you should be able to build over them if you have a bunch of extra builders.

[Clam]

Basically, you keep hammering on the mouse when the builder is near the top of the screen; I think three times he'll stop building before he bugs out on the top of the screen; then if you do it correctly you can release him with a digger, and he'll walk back down the bridge without having damaged it (I couldn't work out the rule for it, but sometimes he dug through the bridge and I'd have to start again).

Interesting, I haven't seen this one before. What seems to be happening is that the stuck lemming bobs up and down slightly (I have no idea why it does this), so if you assign the digger skill at the 'up' part of the cycle, it finds it has no terrain to dig at, and a digger assigned with no terrain in range transitions immediately to a faller.

Sadly (or rather fortunately, given the number of skills involved), none of this is necessary to solve the level. Here's Taxing 8 with just 1 blocker extra.

[finlay]

Oh well. Do I at least get a cookie for possibly discovering a glitch? 

Anyway, would it be possible, minimac, to actually post underneath what extra skills were used? We could maybe then have a go ourselves and try to beat it...

As for Wicked, since nobody's started it yet:
1 requires no skills (like Fun , although it's impossible to get to the top exit.
2 & 3 are impossible
4 is possible via any of four exits – although significantly harder to get them all to go to the NW exit.
I can't work out a way for 5, since there is only 1 bridge (which is enough to get them there from the entrance platform, but some will inevitably fall off)
6 might be possible, if you are able to pull off a bomb-squad style manoeuvre with bomber timing (there are also a few miners which can serve a similar purpose) – however I'm not very good at this and not sure how many builders would be necessary. You can trap the crowd with blockers at the bottom, however, unlike Wild 1 (which I'm pretty sure is impossible)
7 is one of the few ONML levels without builders and is naturally impossible.
8 is possible, and a nice little puzzle as you can only lose 5.
9 is unsurprisingly possible.
I thought 10 was possible, but the death drop was higher than I thought. The solution may yet be salvageable, though, not sure.
11 doesn't look possible to me, and it's a bit long for me to want to attempt.
Fairly sure 12 is impossible
13 is possible.
14 is impossible for me, but I suspect it may be possible to slide up the wall on the left.
15 is possible
16 is impossible
17 seems impossible
18 seems like it'll need a way of turning the lemmings around on the right. Don't quite want to declare it impossible just yet.
19 is impossible.
20 doesn't seem to have enough builders. (and then there's the issue with the exit having to be slightly buried so that it'll save properly in Lemmix!)

[Minim]

By the way, how did you solve We all fall down in the end? What skills did you add?

I realise that the entrances for the Fun/Tricky version and the Taxing/Mayhem version have different y-coordinates. Apologies for that. I'll have to re-work those levels tomorrow so that they look similar. Anyway, for the Fun/Tricky version, I took the right side and I think I used 10 builders for that method.

[Clam]

Oh well. Do I at least get a cookie for possibly discovering a glitch? 

I think only ccexplore can tell you for sure whether this glitch/trick is 'new'. He's been around a lot longer than I have

As for Wicked, since nobody's started it yet:
[...]
2 & 3 are impossible

Wicked 3 is not impossible, thanks to yet more sliding magic.

[finlay]

you and your sliding glitch...

you see i'm still mostly thinking in terms of 'conventional' solutions...

Anyway, confirmed Wicked 10 as possible.

[Clam]

you see i'm still mostly thinking in terms of 'conventional' solutions...

There's nothing wrong with that, conventional solutions work just fine for most levels.

It seems reasonable that the sliding glitch is going to see a lot of use in this type of challenge. There's a tendency for levels to start at the top and work downwards (the alternative usually being heavy building, which would be boring to do all the time). Reversing those levels means you start at the bottom and work upwards. The sliding glitch can be a very skill-efficient way to move lemmings upwards. It makes sense.



Continuing on with more improvements to Wicked:

5: Annoyingly, I couldn't quite pull this off either. At most though, you can get by with 1 added builder.
6: Possible. To start with, I used sliding to get halfway up, but it turns out you don't need to do that. This solution also uses no bombers at all
(I did 10 since my last post, but you beat me to it. Good find )
11: Me and my sliding glitch . It's possible with the regular skillset.
16: Pretty clearly impossible with the regular skillset, here's a fairly simple method using 5 extra skills, 1 blocker and 4 builders. I haven't looked too hard for other methods, but nothing stands out as a better option.
18: Not too difficult, you just need to stack some bridges on the right to contain the crowd.
19: This one works out very nicely with 1 added blocker.


For 14, it looks like you need extra skills just to reach the left wall, let alone slide up it. It might still be the best option (as far as fewest added skills), I don't know yet.
For 20, I suspect the most skill-efficient solution involves sliding into the exit, so it matters not that it's buried
EDIT: Changed my mind. I found a solution with 1 builder added, and no glitches. There's a 'spare' digger, so it still doesn't matter that the exit is buried

[ccexplore]

Oh well. Do I at least get a cookie for possibly discovering a glitch? 

Here. (Surprisingly difficult to Google for blue and green cookies that I'd want to eat.  The above ain't it. )

But yes, while I can't say my memory's that great, I do believe you have reported a glitch that hasn't been reported before.  Good work!

<now go back to game disassembly to see how this is happening...ah ha> Basically this is caused by a discrepency between how the game does the "too close to the top" check, and the vertical position it resets the lemming into in order to keep it from going further up.  It may literally be a mistake between "less" vs "less than or equals".  Basically something like this (except it's not exactly 10 and 9, but I can't be bothered now calculating the actual values in screen coordinates):

if (y <= 10)  // smaller y is nearer to the top
{
    turn lemming around;
    y = 9;
}

Resetting the y is clearly an attempt to keep the lemming in check, but the discrepency between the check for the condition and the reset value pretty clearly leads to the behavior observed, with the lemming bobbing up and down slightly while in its stuck state.

[edit: neglected to mention one addtional detail (though pretty obvious if you try to figure out how the glitch works given what I already told):  the "check and reset" above only takes place for a walker if he's maintaining or moving higher in vertical position.  If the lemming takes a small step down instead, there is no "check and reset" for the top boundary in that case (which indeed is kind of unnecessary if not for the discrepency at the heart of the glitch).  This is why the lemming only gets pinned to y=9 every other frame (ie. bobbing up and down), instead of every single frame.]

[Clam]

Crazy 13 is possible, and made a lot easier because of direct drop (so it only needs a blocker to turn the lemmings round for instance).

That's Crazy 14. 13 is considerably more difficult than that


Here's some more Crazy results:

2: The best I've managed so far is +5 skills, by mining and building through the exit platform.
4: Done with +3 skills, one each of blocker, miner and digger.
6: Annoyingly close to being doable with one skill added, but in the end couldn't do better than +2 builders.
16 and 19 are possible with the regular skillsets, the latter with no small amount of time limit rage.

[finlay]

(I did 10 since my last post, but you beat me to it. Good find )

Same way, or different?

[Clam]

Pretty much the same, including exploiting the poor steel object placement (thank you, Lemmix editor! ), and building into the chain.

[finlay]

OK, here are some Wild levels, starting with the second half:

11: impossible. Best I could manage was 13 extra builders, because you have to build all the way up a tiny gap.
12: possible
13: impossible, and probably very difficult to solve in the time limit. Not sure of the best way to go about it.
14: possible - you have to use bombers to get past the spike traps, however, because you have quite a limited number of builders.
15: impossible, again not sure what you'd have to add to make it possible.
16: impossible, but adding 1 basher allows you to take the route over the water traps.
17: may be possible but I don't want to attempt it because if it is it'll be hard to pull off.
18: again, I don't want to attempt it. I don't think this one is possible, though – eg you'll have to waste a lot of builders to make the right hand side impassable.
19: possible
20: seems to need quite a few more builders than you're given.

8: with a 1-minute timer, may be permanently impossible. Certainly the obvious route of building up took too long.
6: had to add 1 climber in order to get out of the entrance chamber and release (weren't enough builders otherwise)
5: this level pissed me off a little bit because it looks like it should be possible to build up to the left, but with the 4 builders availble, you're 1 goddamn pixel short! Argh. Anyway, it's trivially completable with 1 extra builder, in that case...
4: it may be possible, although the solution I was using ran into trouble and I couldn't complete it without 1 extra builder. I didn't manage to pull it off, however, not quite, because I had trouble releasing the blockers at the beginning. (my laziness/incompetence, not the level)
3: possible, although the exit being buried is annoying (there are plenty of spare diggers but it's easy to forget!)
2: Not sure, haven't tried it but I don't think there are enough builders to get up to the exit
1: Pretty sure it's impossible without blockers to hold the crowd. Haven't tried it though. Like "Pop til you drop", should be possible without bombers (there are only two layers of bubbles to get through)

[Minim]

I've had a turn myself at this difficulty rating as well, and on the ones where you didn't want to attempt I've solved Wild 17. Both that and Wild 14 have turned into beautifully crafted puzzles. On 18 I came close, but not close enough to get through. Looks like we need help saving builders with that special technique which I guess has been mentioned here. It may be possible with 1 extra basher I think. But anyway, Here's a hint on how to trap the lemmings in 17:

A blocker should be set first, followed by the second lemming mining and building to the left (without going off the bricks) to hold the others back. The third lemming is your worker. The blocker can be freed by mining and building to the right (again, without going off). It is quite a tight space! After your worker has made a path, some luck on timing is required as you try to get the lemmings out of your created pit.

[finlay]

Crazy 13 (It's a trade off): I was going to say 20, which is 18 climbers, 1 blocker and 1 extra builder – however, because the level only requires 50% (ie 10 lemmings), the true total is 11 – 9 climbers, 1 blocker and 1 extra builder.

Also I suspect Crazy 17 is permanently impossible, because I can't even get close to the exit with the solution I'm trying to use. I don't think you'd be able to build over the water, which would be a bit quicker than bashing through the ceiling as you do in the forward level.

[Clam]

My turn on Wild:

2: Possible by sliding up the pillars before the exit. Another option might be using Tame 20 into one of the floating platforms, but if anything the sliding method is easier.
4: Possible, and turns out to be a very nice glitch-free puzzle
6: Again, possible with default skills, and another nice puzzle. (That trick may even be worth making into a custom level )
8: Done with +3 builders, would be 2 if there was another 15 seconds or so available.
11: Another great puzzle (albeit glitchy this time), with no added skills needed.
18: Possible. Using ccexplore's improved builder-stacking method, I ended up with 2 builders spare, so even basic builder stacking will do (as long as you start stacking in the right place ).


Also, because I detest the word 'impossible' when it relates to Lemmings challenges, I've completed Crazy 17 with 11 edit: 9 skills added (6 builders, 2 bashers, 1 digger). Even with sliding, this one only just squeaks in under the time limit

[finlay]

Re: 6 – Dammit, I always forget about the possibility of an outside route...

[Clam]

Improvements to the first half of Havoc:

2: I found a way through the ceiling with just 1 basher added. (Steel placement fail again )
3: Done with +3 skills, 1 blocker and 2 builders. This is an awkward one, you can possibly save a builder but it takes a lot of other skills to do so.
5: Done with +2 builders, with great difficulty, unfortunately you can't mine past the exit trigger which would save another builder and a whole lot of effort. (Even in reverse this isn't one of my favourite levels )
6: Beat this one with the regular skillset
9: By building through the edge of the starting platform, I managed to milk enough distance to save a builder. Ended up with 2 added skills, 1 builder and 1 digger.

[finlay]

Minimac, Mayhem 12 is possible – clam completed it the other day.

Crazy 12 can be completed with +4 – 2 climbers, 1 builder, 1 miner.

[Minim]

I had a go at this recently, and I can confirm that I have improved it to just 2 skills. Here's a replay, using 2 additional builders (And also, a basic example of the slider trick  ). 1 skill may be possible, if we expand on this trick, but I'll see if someone else can do that.

[finlay]

the holiday levels are a lot more difficult because less skills have been provided for each level...

in Frost: 1, 3, 5 are possible, 13 requires no skills, and the others are either impossible with the defaults, or hard enough that I can't be bothered trying.

in Hail: 4, 5, 9 are possible, not sure about the others.
I've been staring at 11 for ages, but I think I can only solve it with at least one more digging skill (any of miner, basher or digger should do, although basher would be easiest). You can get to the lower exit with the two miners by letting the first one take half a swing (this is surprisingly difficult to do btw, considering that you guys seem to do it all the time – i had to use the frame advance feature) to get higher up and then mine down again. But you can't use blockers to contain the crowd because you need 100%, so you need to use a digger – except then you can't get past the pole, hence I think 1 basher would suffice to get past the pole. Strictly speaking, this is theoretical and I haven't tried it, but there you go anyway.

haven't looked through the other ratings yet.

[Clam]

I've had a proper look through Fun and Tricky and found a few improvements:

Fun 2 with 4 added skills (2 builders, 2 bashers)
Fun 3 with 8 added skills (1 climber, 5 builders, 1 basher, 1 digger)
Tricky 18 with 4 added skills (2 builders + 2 bashers, again )

On the other hand, Tricky 15 is listed as needing 3 added skills, which I can't match. The closest I could get was 4 (1 blocker, 2 builders and 1 miner). This level doesn't seem to have been mentioned either here or in the reverse level packs topic. I sure hope this score wasn't copied straight over from Fun 1

[Minim]

Tricky 15 is listed as needing 3 added skills, which I can't match. The closest I could get was 4 (1 blocker, 2 builders and 1 miner). This level doesn't seem to have been mentioned either here or in the reverse level packs topic. I sure hope this score wasn't copied straight over from Fun 1

It wasn't. Although it was a little frustrating trying to get the bomber in the right place, I've managed to solve it with 3 additional skills. Using 2 bashers and a builder, I've attached a replay. Also, the first time I defeated Clam Spammer in a challenge!

[Clam]

Well, so much for my powers of observation . You can have an unappetising blue-green cookie too . Still, it's typically good practice to at least report your results rather than just filling in the table, that way we know for sure that it's been done properly.

[finlay]

Indeed, there's quite a lot of results i'd like to know more about in that table....

[ccexplore]

in Frost: 1, 3, 5 are possible, 13 requires no skills, and the others are either impossible with the defaults, or hard enough that I can't be bothered trying.

Reverse Frost 7, 11, 14 don't look that hard.  Actually I've confirmed 7 and 14.  11 doesn't seem to need confirmation.

I've been staring at 11 for ages

It's fairly easy with a glitch using just the original skillset, not sure about more conventional solutions.

[Clam]

Now to remove doubt about some unreported results by rendering them obsolete

Taxing 6 can be done with 2 builders added.
Taxing 7 is possible with the regular skillset.
Taxing 9 is possible with 4 builders added.

[Minim]

Indeed, there's quite a lot of results i'd like to know more about in that table....

OK then, I will tell about the Holiday results that I've recently done:

I've confirmed so far for Flurry that all but 8, 13 and 16 are possible, and I was going to say 12 as well but according to this challenge thread it claims to be possible. May I see a replay of this just to confirm it?

8 is likely to be possible (not with the default skillset though) considering that you have enough time to save at least a lemming and also the fact that you need Clam Spammer's special reverse Taxing 8 100% steel trick. On 13 I used 2 spare builders and 1 digger. Nothing too chaotic at the start, you just had to dig at the right place. For 16 I used 5 spare builders, and also taken the ceiling route to speed things up a bit.

For Blizzard there were quite a few levels that had to be done with more skills than normal. For 2, I have recently improved my efforts to 1 skill. Using another digger, a replay is attached just to clarify.

[Clam]

I was going to say [Flurry] 12 as well but according to this challenge thread it claims to be possible. May I see a replay of this just to confirm it?

Sure. This is actually one of the tougher pixel-counting puzzles you're likely to see, thanks to the lack of builders

[Minim]

Thanks for that well executed solution.

OK, I've done most of the rest of Blitz, and came up with the following results:

3: 7 skills. Using 5 spare builders, 1 basher and 1 miner I used sliding to get some of the lemmings up to the top, followed by building up to a miner's tunnel.
4: 4 skills. I tried all I could to go for less, but can't seem to get lower than 4, primarily because you need 100%.
8: 6 skills. Replay explains what I did.
10: 3 skills. I used 3 extra builders (And some quite precise builder placement too)
11: 13 skills. This was quite a complicated one, as I needed 10 spare builders, a blocker, an extra digger and a floater. This was much harder than it looked...
12: 11 skills. I'm expecting this one to be improved, as I did poorly at trying to manage the slider trick. May need a change of plan though. I should also mention that the exit is buried, so a bomber or a digger could do that.
13: 5 skills. Managed to do this with 5 more builders, I still can't rule out this being done with fewer than this.
15: 3 skills. Works nicely with 3 added blockers.

The ones I'm stuck on are 14 and 16. Also haven't solved Flurry 8 yet, but I'm going to take a break from the '93 levels and work on Frost and Hail, my two rating preferences in Holiday Lemmings.

[finlay]

Blitz 14, "The Undiscovered Country", can be completed with +2, 1 each of climber + builder (remember when climbers are stuck they will start to climb through the rock). I'm not sure if it can be completed with +1 or with the default set.

Re: ccx's replay of Hail 11: oops, missed that. You know when you're so focussed on one solution and being sure it must work that you forget to check other solutions?

[ccexplore]

I worked on Hail a little bit.  In addition to 4, 5 and 9 that Finlay already mentioned, the following levels have been confirmed possible with original skillset:

1, 7, 8, 10, 11, 15

Also, while I haven't actually confirmed, 3 and 14 looks quite possible to me with their generous original skillsets and time limits.

For 6 (the nuking level), I did it with +7 (1 climber, 1 bomber, 5 builders).  One oddity of note with that level is that the entire area underneath the "white line" terrain is steel area, so thanks to the crappy steel-handling methods, you pretty much have to use the blocker to get steel-canceling so that you can take out terrain on the white line (even as the line itself is outside of steel area).

Selected replays attached.

[Clam]

Add Hail 2 to that list. There's just enough builders available to slide up to the exit.

Blitz 14, "The Undiscovered Country", can be completed with +2, 1 each of climber + builder (remember when climbers are stuck they will start to climb through the rock). I'm not sure if it can be completed with +1 or with the default set.

I managed it with +1 climber, thanks to a trick that I don't think has been mentioned in the glitches/tricks threads (and tbh I don't know which one it belongs in). Depending on the positioning of terrain around the exit's trigger area, it's sometimes possible to mine past the exit, without the miner disappearing into the exit, while still leaving intact one pixel of terrain overlapping the trigger so lemmings can exit later. In this case, it works out nicely .

[ccexplore]

I've confirmed so far for Flurry that all but 8, 13 and 16 are possible

Got reverse Flurry 16 to work with original skillset via sliding glitch (plus other tricky bits).

[Clam]

Well this was absurdly difficult, but here's Taxing 1 with the original skillset.

[ccexplore]

reverse Blitz 10 can be done pretty conventionally with the original skillset, even for either exit.

[ccexplore]

Well this was absurdly difficult

Nice one.  Yeah it can get quite tedious when you have to save almost everyone and need absolutely perfect timing.  On some of my recent solutions on other challenges like Mayhem 2 100% builders-only and Taxing 27 lose 3 no bombers, it got to the point where I even tracked the amount of time spent shrugging (thank you text replays).   Also, I'm guessing somewhere along the way you made the mistake of not offsetting the leader by one pixel from the compressed crowd (a great and annoying example of update ordering effects that Simon wrote an essay on)?

[ccexplore]

I managed it with +1 climber, thanks to a trick that I don't think has been mentioned in the glitches/tricks threads (and tbh I don't know which one it belongs in).

I think it has to be considered a glitch, because the reason it works is basically the same reason for the miner glitch.  The expected effective coordinates for the movements during one mining stroke should logically be

from (x,y) to (x+2,y+1) and to (x+4,y+2)   [R]
[+y goes down, x doesn't matter which direction is +]

but with the glitch, it is actually

(x,y+1) -> (x+2,y+2) -> (x+4,y+2)   [W]

In particular, the other miner quirk about being able to skip one-pixel-wide gaps do not apply here, since trigger areas in PC Lemmings always have a minimize size of 4x4.  If the miner's positioning were to behave logically like in [R], then I don't think the trick would've been possible.

[Clam]

Also, I'm guessing somewhere along the way you made the mistake of not offsetting the leader by one pixel from the compressed crowd?

No, that part just happened to work out, and I knew to change the shrugging time if it didn't (and since you have to turn that lemming with a builder, it just comes down to odd/even timing anyway). The real difficulty was finding the solution method in the first place, going through all the various ways of turning around at the start, how to merge enough lemmings, getting past the staircase, possible sliding setups, etc, all with a limited (and varied) set of skills, and compounded by Simon's other essay topic, the time limit. I'd already made a few failed attempts when I posted some other Taxing results yesterday, and gave up on it for a while.

Shrugging time is actually rather useful, it might even warrant a mention in the tricks thread.

[Clam]

I worked on Hail a little bit.  In addition to 4, 5 and 9 that Finlay already mentioned, the following levels have been confirmed possible with original skillset:

1, 7, 8, 10, 11, 15

Hah, I had a go at Hail 10 myself, before seeing your replay, and ended up with a completely different solution. Whereas you went for the close exit, I took the low route all the way to the left exit. The middle exit turns out to be reachable as well (replays attached for both).


edit: Go ahead and mark Hail 3 and 14 as possible, no surprises there.

[Minim]

As promised, I did some Frost levels, and came up with some results. All the odd numbers except for 9 and 15 were possible. I also solved 14 using the high route (i.e. walking over the other 9).
Here are the ones that needed additional skills

2: 2 skills. Done with two extra builders.
4: 14 skills. This was a tough level which I might have to have another go at.
6: 13 skills. Took the high road on this level.
9: 4 skills. Done with 4 extra builders.
12: 5 skills. I've taken advantage of the steel-cancelling glitch on this level!
15: 3 skills. Added 1 blocker and 2 builders and it wasn't too bad.
16: 2 skills. Needed 2 more builders to get up to the exit platform.

The ones that I am totally stuck on are 8 and 10. I'm not sure if either of these levels are considered possible due to lack of time.

[ccexplore]

Reverse Mayhem 21 possible with original skillset via sliding glitch again.

Also, reverse Mayhem 20 can be done with just +1 blocker very easily.

[finlay]

I just managed Mayhem 20 too now that you've told me what to add.

[ccexplore]

Reverse Hail 12 with +1 climber, +1 basher and +1 digger.  Another slide-based solution.

[edit: and +2 for Reverse Hail 13, no surprises there]

[ccexplore]

Reverse Frost 12 can be done pretty easily with +1 blocker, +1 builder, taking advantage of the missing steel at the top.

[ccexplore]

Nothing spectacular, but here's +3 builders as a start for solving Reverse Crazy 18, just to get rid of that silly asterisk on the table.

[edit: also ridding reverse Havoc 17 of its asterisk, with +1 climber, +3 builders, +1 basher as a start]

[ccexplore]

Reverse Havoc 11 with original skillset.

[ccexplore]

Reverse Frost 8 with original skillset.  This requires the pause trick, so to verify it in Lemmix, change the time limit to 2 minutes and see that 93% is reached before the timer reads 0:58.

[ccexplore]

Reverse Wicked 12 with +1 builder, +2bashers.

And reverse Mayhem 24 with +1 climber, +2 blockers, +7 builders, +2 bashers, +1 miner (so 13 total), unsurprisingly with sliding.  This one also needs the pause trick, although I've also found other solutions (but using more skills) that work w/o it.

[ccexplore]

The entrances on the two reversed Just a Minute levels are set too high, it's suffering from the splat-on-dig-pit problem.  I've attached alternate versions of the levels with the entrances lowered as much as possible while still having lemmings emerged aboveground (well more like on-ground), to maximize your available time.

That said, even minimac's original versions can be handled with naive solution involving +50 climbers, +1 blocker and +1 builder, with about 10 game seconds to spare.  I suppose you can put that down as a result although I'm sure you can do a lot better with sliding.

[Minim]

The entrances on the two reversed Just a Minute levels are set too high, it's suffering from the splat-on-dig-pit problem.  I've attached alternate versions of the levels with the entrances lowered as much as possible while still having lemmings emerged aboveground (well more like on-ground), to maximize your available time.

I agree with your idea, and I'll post results based on your improved levels.

That said, even minimac's original versions can be handled with naive solution involving +50 climbers, +1 blocker and +1 builder, with about 10 game seconds to spare.  I suppose you can put that down as a result although I'm sure you can do a lot better with sliding.

Or, we could possibly try and improve it using that special Reverse Fun 5 basher method, if we could turn the lemmings around at the right time.

I'll put those results down anyway. Just to correct you that there is a climber in 27. So at the moment, 16 needs 52 skills, and 27 needs 51.

[ccexplore]

Here's reverse Frost 10 with +1 basher.  So I think we've dealt with all the levels people have worried about lack of time, except Mayhem 3, which Clam said he'll retry after everything else.

And so people don't forget about the other two Xmas games, here's reverse Xmas92 level #2 with original skillset, sliding again.

[mobius]

I love this idea.

Here's a different take on it: [I didn't feel like creating a new topic just for one level, though I may do this with other levels... It doesn't look like this thread is very active right now anyway]

When I looked at 'Call in the bomb squad' I thought; why not put all that decorative terrain to use?
note: I didn't attempt this myself yet, so I'll be interested to see the results

[mobius]

for the steel side I intended to take a few pieces away so you could get through. But right now I think I just put the exit on the right side. Or is the entrance there and exit in the middle? I forget 
Anyway I was thinking of doing that with all the levels that have decorations on the side. I might just make a level pack about something like that.

I should say that I'm terrible with keeping records and I'm generally not competitive at all so don't count on me for that sort of thing.

[Proxima]

Time to get rid of those irksome blank spaces in the table....

Taxing 30/Mayhem 11, unsurprisingly, works with +10 builders, the same as Fun 13.

Save Me is a real pain, but there's just enough time to reach the exit by building until you nearly hit your head, alternating digging and building to get across, turning, then building a reverse bridge to catch the crowd. My result is +17 builders, +1 miner, +7 diggers (25).

Vacation in Gemland also has a huge time-limit problem going in reverse, and I can only do it by making everyone a climber. This is +49 climbers (you start with one), +2 blockers, +5 builders, +1 miner (57).

Blitz 16 can be done by glitching through the steel with +3 blockers, +12 builders, +4 bashers, +6 diggers (25).

[geoo]

Improved Blitz 16 to +1 climber and +11 builders.

Vacation in Gemland can be done without assigning everyone a climber. Solution attached, without any regard for skill efficiency.


Also, I request the star for Mayhem 3 to be removed, as I'm not convinced it's impossible. (I suspect it's in fact possible, but I really don't want to try.)

[Proxima]

To save you the effort of counting, geoo's result for Flurry 8 is 18. I can improve this to 16: (1) At the start, place the first builder exactly so that his fourth brick lies over the 1-pixel gap, saving the next lemming. The builder will run out of bricks just before going over the holding area, saving one basher. (2) Where geoo alternates building and mining to get through the diagonal crystal, instead of the third miner, just let the lemming hit his head and turn, then build to turn him again.

Here's a better way on both Just a Minutes (+1 climber, +1 blocker, +3 builders for 5 on JAM and 4 on JAM2).

[Proxima]

I had another go at Mayhem 29, and improved my result to 16 (1 bomber, 10 builders, 1 miner, 4 diggers).

[Minim]

Bump.

For some reason, I'm having problems getting Proxima's new replay to work. The error comes up with something like 'invalid replay header different mechanics' and I don't know how I can fix this problem. I hope this isn't going to happen to all other replays... 

In other cases, I have confirmed that with an infinite amount of time, "It's hero time" is possible with 8 extra skills, 6 builders and 2 bashers. Not too difficult once you know which route to take.

[Proxima]

My apologies. That replay was saved using Custom Lemmings mechanics. To view it, right-click the level list menu, select "Change viewer style..." and select "Custom Lemmings" before selecting "Save Me" from the level list.

[Minim]

Bump again.

On Taxing 19, I have improved it to 21 skills. Still, I'm sure this level can still be improved, especially by someone who has mastered the bomber sliding trick. The same thing goes for Crazy 12. I used two extra builders on that level (Posted replay earlier) and believe it can be done with just one if that type of trick comes into play.

Edit: I have verified a solution which uses 10 skills (In detail, 3 climbers, 2 blockers, 4 builders and 1 basher). It's very similar to Clam's Fun 18 replay (Why didn't I see it earlier?  ), the only differences being that you make the three free lemmings climbers once the stair is made and let one of them blow up the corner of the left wall to create a ramp for the others.

[Minim]

Some more improvements:

Crazy 3 down to 9 skills (+2 blockers, +6 builders, +1 miner)
Crazy 15 improved to 7 skills (+3 blockers, +4 builders). Needs a bit of teamwork to get the builders in the right place but should be straightforward.
Wild 1 down to 3 blockers, and another example of very basic sliding
Wild 13 improved to 6 skills (+5 builders, +1 digger) Replay just in case
Wild 15 down to +6 builders
Wild 20 down to 4 skills (+3 builders, +1 basher) Quite a fun solution to execute as long as you put the builders in the right place.
Wicked 2 down to 8 builders
Wicked 7 down to 11 skills (10 builders, 1 basher)
Blitz 4 down to 3 skills (2 builders, 1 basher)
Blitz 12 down to 7 skills (2 blockers, 4 builders, 1 basher), and another example of very basic sliding.
Frost 4 down to 12 skills (1 blocker, 9 builders, 1 basher, 1 digger)