I have this giant magic mirror inside a closed room. Working on a clever puzzle that will involve their demons but will be more interactive for the players. Any ideas?
This puzzle is one-dimensional, primarily based on greed, but you can introduce other "sins" as needed -- sloth, lust, gluttony, etc. For the purposes of this encounter, I would rule that Detect Magic works, but Identify does not.
The room is full of "treasure," but no door. Lust might involve a long-lost romantic pursuit, or gluttony the best food and wine EVAR or sloth a welcoming bed or other tranquil environ.
The mirrored reflection shows no treasure, but does have a an exit at the end of a circuitous path which is perhaps fraught with obstacles or even traps.
The players can take/do what they want, but every round they take such an action, a shadow image flits away from their "reflection" next to the exit in the mirror. The shadow appears to have some manifestation of whatever they took/did.
After a given number of rounds, the treasures turn to dust, the reflections vanish and the mirror transforms into an exit. Your shadow is now "out there," doing stuff in your name, until you deal with it. Its level = the number of rounds you spent messing around with the "treasure."
At any time, the solution is to step through the mirror and trade places with your reflection. Whatever shadow you created vanishes when you pass through, but it will still manifest as above. To escape, you must traverse the path to the exit. Your reflection is stuck in a room full of treasure.