Hmmm - "Krell" just popped into my head. Don't have any of the books near me. Am I remembering right that is the floating brain with a BIG beak and tentacles hanging under it? (Did that even make it to 3E. or am I stuck in a previous edition?)
Then again, my mind would probably just refuse to register it correctly (ok, I'm seeing this wrong. *blinks and rubs eyes*). At least until it shrieked - I'm thinking something hawk- or eagle-like, but don't know if that's actually listed in the description or my own personal imagination. Then I think I would be outta' there before I realized it.