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?