I think maybe we could give Sui Generis the benefit of the doubt when we're wondering how enemies respawn. It'd be rather dull to not have enemies come back when you kill them, as you'll eventually just have nothing to do. Imagine you travel from town to quite-far-away-middle-of-nowhere, slaying monsters that ambushed you or whatever, or killing a stray bandit that attacks you. Then, when you've finished your business wherever it is you are and decide to return to the same town, you're just walking down the same path and backtracking the huge distance. Boring, right?
Same for the underworld. Enemies (not the exact SAME enemies in the same place, they should be new enemies maybe showing up somewhere different than before) should come back so you don't end up just clearing a huge area and having an empty ruin left. I think monsters and beasts would move back into the cosy dungeon, no?
Of course, the problem is how quickly they should respawn (edit: I mean how new enemies should spawn). I think maybe it should depend on how thoroughly you cleared an area of enemies. For instance, if you clear a small mausoleum of skeletons, they should be gone for at least several in-game days or weeks. Another example would be possible bandit camps, where, if you kill all (or most) of the bandits there, then they don't respawn and the camp is abandoned.
Of course, just having the bandits respawn in the same camp after a few days all the time would be boring, so maybe have bandits set up new camps every so often, or if a camp is destroyed? It'd be an interesting concept, to be travelling the same path between towns you always take, and then you come across a bandit camp that's been set up since the last time you've been there. Obviously the camp would start off with just a collection of tents, then maybe they set up an outpost and some wooden walls or something, I dunno.
Also, I like saints row 3
. It's daft and silly and fun, and it's awesome for it.
Edit: nice idea for the barriers at the edges of the world! Sounds like it'd be awesome to find an ancient guardian or something and be unable to continue.
However, it should be really obvious (or maybe just stated outright using some lore or something to explain why it's not possible to pass these enemies) that the unkillable enemies signify the edges of the game world. Otherwise some players might obsess about finding some way to kill them and get past, which is impossible, obviously.
also, I forgot to add another point about new enemies spawning, and that is how far away you are from whatever you just killed and how long ago you did so. I think it would probably be a good idea to only have new enemies spawn if it's been quite a while and you're not anywhere nearby, otherwise you'd be all "woah, I just came this way and killed everything, where'd these guys come from?".
