Stonefish

like a pufferfish but permanantly puffed up, but it's brown or rainbow colored and has the poison effect and stun for 10 seconds if you go on it

it's a NPC, can look like a normal rock (the high ground) but smaller (you can actually use it as the high ground if you're immune to poison and stun...)

moves SUPER slow and spawns in the deathlake or the ocean...