TIL you can layer Shark Traps
I don't know how I didn't notice this before. I always assumed it was a waste to spread shark traps over spots that already have them. But it turns out they can layer on top of each other.
If an enemy steps on a spot that has multiple shark traps, they'll spring the first one, and only if it doesn't kill them will it spring the next one, and so on. Once they kill the monster, any that weren't needed stay on the space.
One more reason shark trap is my favourite interfusion.