It didn’t take gamers long to notice that many features in Castlevania II: Simon’s Quest were similar to that of Metroid. The game’s director instead claims it was based on the Konami game The Maze of Galious.
Metroids have made cameos in Kid Icarus from the original to Uprising. They are called Komyato in the games.
In the first two Metroid games, Samus Aran resembled Sigourney Weaver. But in Super Metroid she became blonde, as they based her on Kim Basinger.
Nintendo fans were shocked when they saw Samus Aran had actually been female under the armor in the original Metroid. The ending twist was mostly created because someone thought it’d be funnier this way.
Part of Metroid’s hero Samus Aran’s name is after soccer player Pele whose real name is Edson Arantes do Nascimento.