This is discussion archived from a time before the current discussion method was installed.
Lale: This is much older than a video game trope. This happened to every knight in The Faerie Queene.
Ununnilium: It's not the same as simply "something happens while the characters are sleeping", though.
Document N: The Oni "inescapable dream" example seems different from the rest (although other games have those). Is it a new trope? It's sort like Your Mind Makes It Real, but it's a game mechanic instead of a plot point/device.