This category describes games that have been classified as falling into the Metroidvania genre of gameplay, a specific type of action-adventure game (as well as platform game, generally) that features a large interconnected game world that progressively becomes more accessible as the player collects power-ups. While the name comes from the series Metroid and Castlevania, both launched in 1986, earlier games may be retroactively considered members or predecessors of the genre.