Author Topic: Glitches in Lemmings  (Read 24976 times)

0 Members and 1 Guest are viewing this topic.

Offline ccexplore

  • Administrator
  • Posts: 4971
    • View Profile
Re: Glitches in Lemmings
« Reply #30 on: August 10, 2011, 02:09:02 am »
here's another SMS weirdness I encountered.

The attached screenshot doesn't show it well, but basically, despite the fact that the starting build brick of the bridge in the dig pit isn't actually touching the pit bottom (at least visually anyway), the lemmings will nevertheless be able to walk up onto it.

And as for how I managed to get the digger to start building apparently above ground level, (and also why the pit bottom isn't perfectly flat), I think it has something to do with my use of pausing.

Offline Pooty

  • Posts: 324
    • View Profile
Re: Glitches in Lemmings
« Reply #31 on: August 15, 2011, 01:52:08 am »
Whoa! Here's one that startled me. In my everlong quest to get 100% in Fun 11, something odd happened when I used Dega's auto-fire pause button feature. The basher began to bash through the one way wall from the right-hand side, then all of a sudden, he slid right through it! I imagine it involves rapid pausing and unpausing during the frames that shift the lemming forward, but other than that, I have no idea what's going on here.

[Edit] But whatever's going on... I like it! It's enough to rescue 100% on this level! :D

[Edit 2] And now I have a video of the glitch.

Fun 11 - 100% Solution (SMS Lemmings)
SEGA Master System version
100% on 110/120 levels (92%). Other levels [Lemmings lost]:
Fun 03 [3], 06 [2], 18 [5]   
Taxing 19 [5], 27 [1], 28 [3]
Tricky 15 [5], 17 [2]
Mayhem 19 [7], 26 [10]

Offline ccexplore

  • Administrator
  • Posts: 4971
    • View Profile
Re: Glitches in Lemmings
« Reply #32 on: August 15, 2011, 09:55:33 am »
Wow, kinda like a horizontal version of the sliding glitch.  Awesome! :thumbsup:

Unfortunately I'm not using Dega at the moment for emulator, will need to either replace my emulator or find the equivalent feature there.

It would be great to find out how powerful this glitch could be, for example, I wonder if it's possible to get the lemming to continue sliding even while there's no ground for him to stand on? :o

Offline Pooty

  • Posts: 324
    • View Profile
Re: Glitches in Lemmings
« Reply #33 on: August 15, 2011, 11:38:27 am »
It's quite hard to test this glitch out because it's difficult to pull off and maintain. From what I can tell, he'll stop sliding if he's no longer on ground. He might also stop sliding if he runs out of bashable wall, but again, that might be me running out of luck.

Oh yeah, and the pause-unpause rate has to be greater than once per frame.

[Edit] If the game is paused as the game reads the address $36F9, you'll stall the basher. If the basher's frame count && $07 is equal to 5, the basher will slide, provided that the game is unpaused by the time it gets to $3F3B (I think). The pause variable is stored at $DACF.
SEGA Master System version
100% on 110/120 levels (92%). Other levels [Lemmings lost]:
Fun 03 [3], 06 [2], 18 [5]   
Taxing 19 [5], 27 [1], 28 [3]
Tricky 15 [5], 17 [2]
Mayhem 19 [7], 26 [10]

Offline Pooty

  • Posts: 324
    • View Profile
Re: Glitches in Lemmings
« Reply #34 on: August 15, 2011, 10:33:28 pm »
Okay, I've set up a hack that allows you to perform this glitch by simply holding the 1 button down while a lemming is bashing. Using a hex editor, go to $3700 and replace the bytes (which should currently read DD 7E 07) with:

Code: [Select]
C3 1C 77
Now go to $771C, and paste the following bytes there:

Code: [Select]
3A D0 DB A7 CA 2D 77 DD 7E 07 E6 07 FE 05 CA C1 37 DD 7E 07 C3 03 37
Now that it's a lot easier to perform this glitch, I've found that you can't do this if you're too close to metal blocks or one-way walls (if you're facing the wrong way), and the slide will continue until the lemming runs out of terrain. In fact, the lemming quite frequently gets stuck at the end of it.
SEGA Master System version
100% on 110/120 levels (92%). Other levels [Lemmings lost]:
Fun 03 [3], 06 [2], 18 [5]   
Taxing 19 [5], 27 [1], 28 [3]
Tricky 15 [5], 17 [2]
Mayhem 19 [7], 26 [10]

Offline ccexplore

  • Administrator
  • Posts: 4971
    • View Profile
Re: Glitches in Lemmings
« Reply #35 on: August 16, 2011, 01:52:10 am »
Now that it's a lot easier to perform this glitch, I've found that you can't do this if you're too close to metal blocks or one-way walls (if you're facing the wrong way), and the slide will continue until the lemming runs out of terrain. In fact, the lemming quite frequently gets stuck at the end of it.

That makes some sense, even from the video, it clearly looks like the lemming is stuck in that phase of basher that moves him forward, while skipping over other phases that does the actual bashing, collision checks, etc.  The only thing slightly confusing to me is that you said it doesn't work if you are too close to unbashable obstacles, yet in your video, it looks rather like you start off right next to the OWW facing the wrong way?  I guess the obstacle checking works a little differently on the SMS version.

Any chance you can find out if similar feat can be performed with the other skills (eg. mining, digging, building)? :o

Offline Clam

  • Posts: 2188
  • Smiley: :8():
    • View Profile
Re: Glitches in Lemmings
« Reply #36 on: August 16, 2011, 06:50:25 am »
Wow, Pooty, nothing stops you from getting 100% - not even undiscovered glitches! Now that's what I call determination ;P :thumbsup:

Offline Clam

  • Posts: 2188
  • Smiley: :8():
    • View Profile
Re: Glitches in Lemmings
« Reply #37 on: August 16, 2011, 10:33:35 am »
I finally got around to testing something that was brought up a while ago:

Using a hex editor or Lemmix, you can set release rates above 99, up to 250. RR100 releases one lemming per 131 frames (effectively RR-156), and 250 releases one every 56 frames (effectively RR-6). When starting with a 100+ rate, you can turn the release rate DOWN towards 99. The rate displays as 99, so it is difficult to tell exactly what the current rate is. RR99 behaves as normal. A release rate of 0 is also possible - this acts the same as RR1, and displays as blank.

I'm pretty sure it's actually 255 not 250.  Also it's possible to make RR 0 (displayed in the game as blank I think, rather than 0), although that's equivalent to RR 1 and therefore not that interesting.


What I've found through testing in DOS (using nocdlem):

- The maximum release rate is indeed 255, and not 250. Lemmix won't open or save a level with RR over 250, but you can bypass this by inserting a hex-edited level file into a levelpack.
- RR255 is equivalent to -1, as expected (the values just "wrap around" into negatives)
- For rates over 100, it displays junk characters (in some cases blank) in place of the first two digits.
- The release rate can never be decreased from the initial value, despite what Lemmix suggests. (There goes that level idea :XD:) It can be increased through the remaining "junk" values, then through 0 and into "normal" RRs, up to 99.
- RR0 displays as blank, as in Lemmix.
- If the initial RR is 255, the two RR values (initial RR and current RR) blink. Increasing the RR will stop the current value from blinking, but not the initial value.

Offline Pooty

  • Posts: 324
    • View Profile
Re: Glitches in Lemmings
« Reply #38 on: August 16, 2011, 11:01:55 am »
That makes some sense, even from the video, it clearly looks like the lemming is stuck in that phase of basher that moves him forward, while skipping over other phases that does the actual bashing, collision checks, etc.  The only thing slightly confusing to me is that you said it doesn't work if you are too close to unbashable obstacles, yet in your video, it looks rather like you start off right next to the OWW facing the wrong way?  I guess the obstacle checking works a little differently on the SMS version.

Any chance you can find out if similar feat can be performed with the other skills (eg. mining, digging, building)? :o

If you're too close to the metal block or one-way wall, it won't work. The lemming needs to stand at least half the crosshair's width away in order to be able to slide through it. Too far away, and there will be no wall for the glitch to kick in with.

As far as I can tell, pausing stalls the builder, while miners and diggers leave behind terrain.
SEGA Master System version
100% on 110/120 levels (92%). Other levels [Lemmings lost]:
Fun 03 [3], 06 [2], 18 [5]   
Taxing 19 [5], 27 [1], 28 [3]
Tricky 15 [5], 17 [2]
Mayhem 19 [7], 26 [10]

Offline Clam

  • Posts: 2188
  • Smiley: :8():
    • View Profile
Re: Glitches in Lemmings
« Reply #39 on: August 17, 2011, 05:27:09 am »
I'm finally having a proper read-through of the thread, and gradually updating the OP. :)


I'd say the behaviour finlay mentioned (climbers turning around at blockers) is intended behaviour, or at least semi-intended, in the same vein as turning builders or miners. Flipping through a wall is definitely a glitch though :P

Now you mention that, I vaguely recall being able to flip a basher through a wall without breaking it.

Sure enough, it works. The attached screenshot shows a basher flipping through a wall without breaking it.

Offline Clam

  • Posts: 2188
  • Smiley: :8():
    • View Profile
Re: Glitches in Lemmings
« Reply #40 on: August 17, 2011, 07:07:06 am »
Finally downloaded and started playing SMS lemmings.  Here's a glitch (attached as zipped AVI file) I found [...]

I downloaded the video, but it won't play because it needs a codec. Where does one get this codec from?

Offline Pooty

  • Posts: 324
    • View Profile
Re: Glitches in Lemmings
« Reply #41 on: August 17, 2011, 12:12:55 pm »
There's a video codec that you can install when you download Kega Fusion. That's the one you need.
SEGA Master System version
100% on 110/120 levels (92%). Other levels [Lemmings lost]:
Fun 03 [3], 06 [2], 18 [5]   
Taxing 19 [5], 27 [1], 28 [3]
Tricky 15 [5], 17 [2]
Mayhem 19 [7], 26 [10]

Offline ccexplore

  • Administrator
  • Posts: 4971
    • View Profile
Re: Glitches in Lemmings
« Reply #42 on: August 17, 2011, 12:27:54 pm »
Whoops, sorry, didn't realize the AVI require the codec.  I'll remember to do a conversion next time.

To be fair, the video is not really that impressive, but I've attached the codec if you want to see it.  Unzip, right click on the file named "KegaGameVideo", and select "install".  (OK the "unknown publisher" security warning popup.)

Offline Clam

  • Posts: 2188
  • Smiley: :8():
    • View Profile
Re: Glitches in Lemmings
« Reply #43 on: August 18, 2011, 08:52:50 am »
Oh, it's the one that comes with Kega Fusion. I tried to install that and I got a pretty nasty-looking warning about "Windows Logo testing" :-\. Do I need to worry about that, or is it just Windows being paranoid?

Offline ccexplore

  • Administrator
  • Posts: 4971
    • View Profile
Re: Glitches in Lemmings
« Reply #44 on: August 18, 2011, 10:30:27 am »
You can ignore that as well, it's safe.  If you feel paranoid just put it through a virus scanner (mine certainly didn't find anything).