WarioWare - Games within games

The closest thing to this I can think of is the Simpsons Game from 2007, in which the Simpsons realize they're part of a video game, derail the game's intended narrative about fighting Kang and Kodos and infiltrate a factory where they play through several other unfinished games based on their franchise, before transcending this reality as well and challenging God Himself to a series of divine video games, all of which is then revealed to be part of a video game played by Ralph Wiggum, who then realizes that he is part of the game being played by the human player.

That game was really ahead of its time; it was crazy back then to see such an elaborately metafictional storyline in a commercially released product.