Metroid is a series of video games made by Nintendo. The series started in Japan in 1986. Its main character in the game is Samus Aran. Almost all of the games in the series have a certain kind of fictional creature called a "Metroid". This is where the name of the series comes from. Metroids look a lot like jellyfish except they can fly. They also have teeth instead of tentacles. They attack creatures and people by charging quickly towards them and sucking out all their life force.