Perhaps a game of living checkers or chess? Where the Trickster either makes them use themselves as pieces or he uses some sort of human thralls. Make the game dangerous and have them either want the human thralls to live or just save their own skins if they are the pieces. You'd have to work out the specifics, but the idea seems to fit your theme.
Ooo I like that! It's better than what I was thinking of with just stealing a bit from Sucker Punch:
have them air dropped onto a castle with goblins and knights or whatever and have to infiltrate the dungeon to get to a sleeping baby dragon, slice it's throat open and remove a fire spewing gem. After that, make their way back out to be picked back up. Oh, and do all of this without attracting the attention of the mother dragon. These would of course be dragons entirely unlike that which we've seen in Dresden thus far but this is a one shot that probably will never be revisited and past that, it's easily explained by saying that all of this is just a product of the demesne the Trickster created.
Either way, killing a baby and being in that much danger, they may well think their chances better with the Tickster.
Still, that seems a little... I don't know? Forced? Great for an action movie or D&D but not so great for this. Still, I think I may well use that idea. Thank you very much. Any other ideas are always appreciated even if I don't use them. Just for future reference (I love sending my players to play in the nevernever.