So I have my party in a sort of dimension that is created by a villain who is a master of illusion and trickery. The setting of this campaign is heavily taken from the Eberron expansion (as well as being a bootleg bioshock infinite with floating cities lol).

The situation currently is that the party are on a train that is infinite, thry don’t realise until they notice certain repeating things. They have to solve puzzles to get out of it but when they do they end up in an infinite hotel and have to escape that too. If it helps, there’s an NPC who is sort of a Cheshire Cat character that gives clues and wares to the players but never directly helps them with anything (he’s true neutral). He’s mischievous and also a watcher of sorts, hiding in places and messing with them.

I am completely stumped on puzzles to think of for this sort of scenario, and anything I find online is too vague to help me. Your help is greatly appreciated!