This is more of a suggestion than an issue, but crabs should be aggressive in the same way Quark's crabs are, in that they are basically just mobile ground hazards; they attack only when you walk on them or if you attack them, and if you do attack them, they're only aggressive for as long as you're close? If that makes sense. I suppose this behavior would be very similar to how Big Cats work, neutral as long as you keep your distance