What levels cannot be beaten with their default release rates?

[Minim]

Another one: Yo-yo Lem Lem from Holiday Lemmings. You need 80, and only 76 lemmings come out after the time is up.

[Proxima]

Crazy 5, 8, 10 and 12 are impossible as the last lemming cannot even enter. It's true that 8, 10 and 12 don't require 100%, but they all require over 90%, and given that the last required lemming must journey to the exit, I'd say there's no doubt they cannot be done.

Crazy 15, 17, 18 and 19 all have 50 lemmings, 3 minutes and a low RR. The last lemming can enter but certainly won't reach the exit on 17. The others should be tested.

The remaining Crazy levels are certainly possible, as are all of Tame.

[Proxima]

Heh, I know this is a really old topic, but I thought, why not finish it off?

Crazy 18 is impossible, hardly a surprise in view of the long path to the exit. Crazy 15 is possible, and 19 is possible by the ceiling route.

On the Mac, Wild 5 max% is just possible -- the last lemming out makes it to the exit just as time runs out. This means that on the PC version, 80-lemming levels with RR 1 and 4 minutes or less will be impossible. So, Wild 2–6, 8, 10, 13, 14, 17–19 are ruled out. Wild 11, 12, 15 look borderline; I'll test these...

...success on all three, but 12 and 15 are so tight (~10sec left) on Mac that they are probably not possible on PC. I don't actually know how big the speed difference is, so this is just a guess

The remaining Wild levels are all possible.

Wicked needs no testing; every level is obvious one way or the other. The impossible ones are 1, 7, 13, 14, 19, 20.

Havoc 1, 11–14 and 17 are impossible. 4 is a special case due to the extremely long time taken climbing all the pillars, but this is possible on Mac. The only other one that needs testing is 19... success. But this one is also very close, about 15sec left.

In total, that's at least 30 impossible levels in ONML, compared to only five in Lemmings.

[Crane]

Hey guys - thought I'd get back into Lemmings and level design!  (I'm the guy that did Garjen years ago)

For a specific version of Lemmings, the level "I am A.T." from the Mega Drive version ("SUNSOFT Special 2" on the SNES) I believe is impossible to complete without upping the release rate (100 lemmings, 01 Release Rate, 2-minute timer).  In fact, you need to up the rate to about 75 just to perform the conventional solution.

Some levels are indeed passable on some platforms, while impossible on others.  On the Acorn Archimedes version of Lemmings, a release rate of 1 causes lemmings to be spaced about twice as far apart as they are in other versions, which I believe makes We All Fall Down (Tricky) impossible - on the DOS version you have about 30 seconds left.

[Proxima]

Now that I finally have Lemmix, it's time to wrap this up with a list of confirmed results rather than guessing based on the Mac version

All the Taxing levels I mentioned as needing testing turn out to be possible, though 8 (which requires 100%) comes down to the last second.

Wild 2 and 10, which I ruled out, are actually possible since both only require 75%. Wild 19 (81%) is only just possible -- you need to free the blocker (or do without one) or you won't make it.

I was right about Wild 11, but it's closer than I thought -- it requires 49/50, which you can get, but the last lemming remains out in the cold! Wild 12 is possible, and 15 is another one that's very close -- you need a lose-4 solution or better.

Havoc 4 is possible with a second to spare, by taking the floor route and building over the tunnel to keep the crowd together. (This is in contrast to the Mac version, where the normal solution to the level finishes in time.)

Havoc 19 fails on DOS; the last lemming (100% required) enters in the last second and cannot possibly reach the exit.

So, here's a complete list for the DOS version. This is a list of impossible levels, not a list of possible levels as in most of the other challenges An asterisk indicates that a level is possible on the Mac. Brackets around Mayhem 15 indicate that it's possible on both DOS and Mac, but not Amiga.

Fun - none
Tricky - none
Taxing - 3, 30
Mayhem - 11, (15), 16, 27

Tame - none
Crazy - 5, 8, 10, 12, 17, 18
Wild - 3, 4, 5*, 6, 8, 13, 14, 17, 18
Wicked - 1, 7, 13, 14, 19, 20
Havoc - 1, 11, 12, 13, 14, 17, 19*