So I had these twins, that should both count as raccoon, but I didn't get the achievement. And my internet is working just fine, so that shouldn't be the problem.
I had this exact idea!! The fourth rank would be perfect for ex. killing of your tribemates that you dont want to banish so they could steal your food sources!
Ability to hurt other tribemates, without having to banish them first.
Could be used to get rid of unwanted tribemates or children without them running away and stealing your food, because u had to banish them.