Brainstorming Backwards Time Castle

Inspired by Dark Cloud, specifically Dark Cloud 1's endgame dungeon Gallery of Time

The Castle starts run down in the 'present', and as the player goes further into the castle, it regresses in time. Most visible in the castle itself, with shreds on the wall becoming elaborate tapestries, tatters on the floor returning to expensive carpets, less cracks in the walls, and overgrown plants receding.

As one goes back in time, the castle becomes less run down, the shreds on the floor become carpet and far less overgrowth

Dragons that go from full grown to just hatchlings, and so do other creatures

Palace Guards, probably not present in the earlier 'later' levels due to being long dead, or they're zombies and not as effective, vs. in the later levels being closer to the prime of their lives.

Golems/ Statue Enemies that don't change much combat wise, only in the later levels becoming cleaner and polished as the rigors of time haven't taken their toll

Time weapons which can either forcefully age or regress an opponent, either to render them to bones or a hatchling.