We are considering the gameplay mechanic first of all, and if it gets accepted, then we will consider how to "flavour" it, just as we did for the new skills.
Sure, but the mechanics for each idea
are different, so there needs to be two separate topics, ideally:
Mechanic 1 (this topic) - Object that has "an effect similar to that of the Bomber skill" (quote from OP), perhaps best depicted as a detonated explosive. This is the only mechanic that should be being discussed in this topic, since that is the one originally proposed. Any other mechanics need to be posted as a separate suggestion/idea.
Mechanic 2 - Object that destroys only its own area and nothing else, perhaps best depicted as locked doors. Needs a separate topic because it's a completely different idea from the one proposed. Even if the original idea is rejected in favour of this idea, it is still a separate idea.
IMHO, the original idea needs to be either accepted or rejected before moving on to a variant or re-interpretation of that idea, otherwise it has basically been ignored.
To be clear,
I am in favour of Proxima's idea. But I am also in favour of an object which destroys surrounding terrain, so I'd personally like to see both ideas being considered independently of each other rather than as mutual exclusives.
What does this offer, that simply locking the exit (and placing buttons), and/or using pickup skills, doesn't? To be clear - in this case, I am not implying "there isn't anything", rather, I am implying (or now, just stating) that I haven't thought much about that either way and it's time to start doing so.
It depends which idea you're referring to.
If the Dynamite object (i.e. the one that destroys terrain), then there are clear and obvious differences between this and a lockable exit/pickup skill; neither of the latter directly affect the layout of the level, and it is still yet to be decided whether the dynamite should be fatal to surrounding lems (I still think that they should "jump" out of the way upon detonation).
If the "Locked Doors" object (
which currently doesn't have its own topic and probably should), then perhaps there aren't quite as many obvious differences, although it does allow for larger and more complex levels, and could also allow both joint
and disjoint union concepts to appear simultaneously.