As we already got some mythical creature - Troll - would be nice to see another one - goblin.
It should be really small and has low hp. Should run away, if you get close. Just like rabbit (maybe not as fast, but faster than squirrel). And it should had a backpack (3x3, maybe even equipable, or just like giftbox). And this container may have some random stuff in it from "land lost pool" (all the things lost in the land, not water) and some random precious small things.
In addition, it could steal some stuff from unlocked containers and transfer it to the pool.
Could be fun. Or not. Tell me.