Key Dee

Key Dee is an awfully villainous rascal who loves running off with keys, especially in a very specific manner so as to constitute part of a puzzle or race. They don't seem to know what's going on around them and always either run forth in a straight line, turning and jumping when they need to, or just stand in place. Although they're enemies, their goal isn't really to hurt Kirby, just to stop his progress by not letting him get the key he needs. To this end, Key Dees are perfectly fine with sacrificing themselves by running straight into lava or spikes, both of which destroy keys, unless Kirby gets there to kill them first. No matter what happens, there's no saving Key Dee. Actually sometimes Kirby can manipulate them so that they use their keys to open doors themselves, but that only makes them jump into the foreground, never to be seen again. I don't really know what happens to them but like there's no ground out there so I'm assuming it counts as a bottomless pit and they die. Key Dees have no self-preservation instincts.