Here is my new Lemmix level, called "The Crystal Coves".

I have tested the level in both vanilla Lemmix and Custlemmix. In vanilla Lemmix it works flawlessly , but in Custlemmix the water and the owws appear a little misplaced. I will try to fix this issue the following days ,by releasing a fixed version for Custlemmix. Also the replay for vanilla Lemmix doesn't work properly in Custlemmix and vice versa. That's why I have posted here replays for both vanilla Lemmix and Custlemmix .

I have tested the level on "custom lemmings" viewing style.

Also both the replays are viewable on  "custom lemmings" viewing style.

I think this is a great idea, and I think the best way to implement it would be to divorce it entirely from the "slippery terrain" implementation*, and have it as a field (maybe a "poison cloud" indicated by purple speckles?) that prevents skill assignments inside the field. You could still have the "destroy terrain to restore skill usage" effect by destroying terrain under the field -- but the initial skill assignment to achieve this would have to be outside the field.

I can see this having a lot of puzzle usage.

* In discord, namida made a good point about this: the snow tileset already has icy terrain that is not slippery, so if we introduce slippery terrain now, the existing ice will be confusing.

I've been playing around with the Spear Thrower a little yesterday, and here's one interesting thing I've found out about how it behaves in L2:

- if you throw a spear into a wall and then climb it up, the lemming will actually climb through the spear from the bottom; but when he hits the ceiling and falls back down, he will walk on top of the spear

That's a bit surprising.  Are we talking regular climber or rock climber?  Any way to see some screenshots or a video (eg. angle of spear)?

With a rock climber and a suitably angled spear, I could see the rock climber climb around the angled underside of the spear to reach the top side, but that's quite different from literally going through the spear.

If the spear touches the wall low enough, I can see a regular climber ignoring that low point of intersection when it started climbing (ie. its head is already above the spear when it started climbing), but that also doesn't sound like what you are describing either.

I think most people would likely consider the described Lemmings 2 behavior unexpected and buggy.  The only way it makes sense is if in Lemmings 2 and unlike Lemmings 1, they more generally added some overhang tolerance for the regular climber so that it doesn't fall as easily.

If all of these answers are no, however, that would reduce the versatility of the Spear Thrower - and therefore its range of applicability - drastically.

Maybe, but it doesn't really need all those extra corner cases to be useful IMO.

But it's interesting you point that out.  Even in Lemmings 2 there is at least one interesting interaction I know of, that makes sense in real life but might not be necessarily expected by the player:

While I was reading the topic on the viability of L3D blocks (https://www.lemmingsforums.net/index.php?topic=4513), one that was brought up which showed some potential was ice / slippery blocks. For those unfamiliar, how they work in L3D is when a lemming steps on a slippery block, they slide along the surface in a forward direction until they reach the end of the slippery surface. During this time, they cannot be assigned any skills that would require them to stand still. So while there is outwardly a "wheeeee, sliding on ice~" factor, mechanically what they're mostly used for is to block skill usage when lemmings are standing in certain positions.

What I want to propose is a more general case. Rather than having it be ice or slippery surfaces in particular, I think there is potential in NL including some kind of terrain type, surface, object or field which prevents lemmings from being assigned new skills while they're standing on it, inside it, etc. The main applications include:

* As a puzzle element. A puzzle with an obstacle that would normally be trivial to overcome can be made more difficult or interesting by forcing the player to take a different route. A simple example: a small ledge can be built or fenced up, but if there's an anti-skill surface/field at the base of the ledge, the player will have to find another way (e.g. getting a lemming atop the ledge and mining down).

* As a way to prevent shortcuts, or to cover backroutes. This also provides an alternative that would allow the designer to keep these skills in play while preventing their use at this particular obstacle. Continuing from the above, perhaps the designer really wants to use a fencer in another part of the puzzle, but its presence allows them to shortcut to the exit through a ledge. They could place a surface/field at the base of the ledge that blocks this course of action.

In L3D, ice doesn't prevent the usage of bombers. In fact, some puzzles make use this fact in their intended solutions by having the player bomb to destroy a piece of ice, creating a surface they can use other skills from later. To that end, I'm most strongly in favor of something like how NL's one way walls work, where it's an object field that is visibly applied to terrain. If a lemming is standing on it, their skills are blocked. However, this terrain can still be destroyed (unless it's steel), which means an additional avenue in puzzle designs is having the player find a way to destroy the terrain to restore the usage of their skills in certain places.

Another possibility that the affected surfaces could become unclimeable/unshimmiable. That could be a whole discussion in itself.

What are people's thoughts?

Ah, so the Laser Blaster explicitly doesn't count as "projectile destruction", only as "range destruction", I guess? That would make sense.

I'm having a bit of a hard time seing how the Mortar (shooting diagonally upwards) would be more useful than the Laser Blaster, given that it still only creates a tiny crater, compared to the long tunnel the Laser Blaster can create.

I guess you can shoot a dent into a wall so that a Climber can climb into it, rather than having to waste a second Climber to bomb that dent into the wall... but the difference between the two seems very minor: If you need to get a lemming to that position anyway (=the Climber who climbs into the Bomber / Mortar hole), then the range of the skill doesn't really give you any advantage. It's only a difference between getting one vs. two Climbers up the same wall.

The Bazooker with his straight horizontal trajectory seems a lot easier to navigate. Since we don't have tumbler physics, it could also be used at close distance without that annoying knockback - which would basically give us the Flame Thrower / WillLem's Lightsaberer in the same breath (=producing a non-lethal, Bomber-size crater right in front of the Lemming).

Then again, if we think of the Bazooker as similar to Flame Thrower and Lightsaberer, neither of those two skills would have added anything new.

The range of course is the new part, but given the type of destruction Mortar and Bazooker create (=a Bomber crater), they still seem a bit like yet another "non-lethal version of a lethal skill we already have".

The most curious use I can imagine would be to free a Blocker at a distance, by shooting away the ground beneath his feet. Meaning, there would be a Bomber crater under the Blocker without the Blocker actually dying!

But unfortunately, most of the time, this would require the projectile to fly downwards (i.e. pass through the Blocker himself and then hit the ground beneath him). So it could probably only be achieved with the parabolic curve of the Mortar's projectile. And using this upwards-shooting skill to make holes in the ground is precisely what you have to do on that L2 Beach level ("Sand Blaster") that kind of spoilt both the Bazooker and the Mortar for me...