It's in the module as an appendix, as is all the action on the island. And as you would expect it is very deadly indeed. You can run it as a prelude to the main dungeon but we would only recommend doing so if you are only playing with one player and they have an expendable character!
If you are playing as part of an ongoing campaign then we recommend that you use another reason they are competing in the Trial of Champions.
I playtested the dungeon section of Trial of Champions (and one other module not out yet - so I won't name that one). But only two of the players involved in that PT are in my main D&D game.
My point was that I hadn't realised they ToC and Sorcery2 were out. I must have missed the posting about them.
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Love is what we're born with. Fear is what we learn here.