The Drunken Lizard Pub

I'm at the last level (I think) of Lair of the Emayu Witch and I'm at the part where you have the lever floating in space outside the room, & I can't figure out how to get the gate open.

I've tried:
Spark spell
fireball
compress atmosphere
reveal map to see if there is a secret passageway???

Can I get a hint? Am I looking at the wrong place?

The lever is accessed from another room. If you talk to the witch then you are close.

Have you met Biezel yet?