Multiple rooms of small puzzles needing to be solved. Nothing quite as demanding as some escape rooms, but enough to take a few minutes.
Some climbing, multiple floors of 1-2 rooms each, some items that need to be carried across multiple rooms, keys that only open certain locks, make the whole thing timed or you "die" and its game over. Some items will be missable, and rooms will close, so its possible you actually can't finish it if you don't time everything right.

Every quarter I'll mix up the decorations and change the locations and solutions to the puzzles to make it interesting every time you wanted to go.

And I'll have a "loading screen" hangout at the start/end of the course with snacks, drinks, some small pinball/arcade games. A couple of TVs with some casual multiplayer games hooked up to it and a few with espn on it. So people could come for the dungeon, and hang around/eat/play until their turn is available, or just come and hang out, host a fantasy draft or watch party, etc.