Spoiler (click to reveal)
Level 3, Tink, Cthulhu, Lighting and Circles.
This was an insta-fail yesterday. But I think I know why. Bottom-line is that this requires sacrifice. I'm thinking:
1) Two characters with enhanced move and rocket boots go for the pressure plates. Invisibility and Moon Rings and stamina potions.
2) The other two characters, preferably ith a summons or two, act as a diversion in the centre room.
3) The danger is the imps and the flame demons. Range, curse and ranged retaliate means there's no chance if you get embroiled in combat.
You either win this one very quickly or you don't win it.