Ridley (Metroid)
Often considered one of the most memorable Nintendo villains, Ridley has been a mainstay of the series, having appeared (through various incarnations) in almost every "Metroid" game to date (all but "", "Metroid Prime Hunters" and ""). He has also appeared in the "Super Smash Bros." series, however, he had not been made a playable character until "Super Smash Bros. Ultimate" in 2018, making it also the first game overall to have Ridley as a playable character.
Metroid
Metroid is a science fiction action game franchise created by Nintendo. The series is primarily produced by the company's first-party developers Nintendo R&D1 and Retro Studios, although some games have been handled by other developers, including Fuse Games, Team Ninja, Next Level Games, and MercurySteam.