Right, now to address the elephant in the room. Well, the Giant Ape actually.
First it's, well, giant! It's flippin enormous! And yet it can't be seen behind a spawnling. I am going to say that only walls, closed doors and blocked passages obstruct you seeing it.
Secondly, this giant ape with massive muscles and a huge club has ...drum roll....4 attack dice

I feel embarrassed for it. Its very clever though, but obviously not enough to learn how to fight. My quick and easy fix is just to swap the attack and mind stats. This still feels underpowered, but is better, and makes it the strongest monster.
Thirdly, I love the Giant Ape!