I think it's relatively common to the RPG genre to have multiple levels going on in a game. Minigames are a hallowed feature of most Final Fantasy installments,

I think it's relatively common to the RPG genre to have multiple levels going on in a game. Minigames are a hallowed feature of most Final Fantasy installments, for example. Crafting might also be considered somewhat of a game. _Fractal_ design, though, implies some element of self-similarity between the levels – and that definitely seems like something more rare!