If you are a member of Blackmoore's Inquisitorial Guild, stop reading.

I don't think any of my players are on Lemmy, but better safe than sorry.

A couple sessions ago, my Dwarf Fighter drew a weapon on a member of the administrative staff of a very prominent magic school. The school is a part of an overarching guild of magi who have branches in all the major cities, and are treated as their own sovereign body. Largely, offenses against the magi are dealt with by the magi, and the state doesn't get involved.

Unfortunately for the dwarf, this staff member has a kind of... Umbridge-esque relationship with discipline. The player has been placed in a magical dream-state to "learn his lesson," the lesson being "I will not incite violence within the school." His guild mates have devised a plan to get him out... by convincing the staff to let them join him in the dream.

His punishment is to face off against a goliath of a man in a colosseum, fighting for his life. If he dies, he wakes up by the colosseum entrance for processing, to be brought back in for the next fight.

The monstrosity he is fighting cannot die, but if brought to 0 enters a sort of stasis where he regains his health slowly, allowing for planning time. Or time to run! He is powered by a crystallized shard of a dead god's soul that the mages are using as a source of nearly infinite magical energy. This is an object of interest for the party.

My struggle here is in thinking of an engaging way for them to acquire said gem and shut down the dream from the inside. Any ideas?

The gem does not have to be physically on the jailer. The solution does not have to involve heavy combat, but it is a welcome addition. The Human Fighter loves a good slog-fest.

Sorry for the wall of text, and thanks in advance for any help!