Ridley (Metroid)
Ridley returns in his Meta form once again in "", where he, along with the Space Pirate legion under his command, are corrupted by Dark Samus. He encounters and battles Samus on Norion, a Galactic Federation-occupied world, and the two fight while free-falling down an air shaft. Ridley is later supercharged with Phazon, becoming "Omega Ridley", and is charged with guarding the Leviathan Seed on the Space Pirate homeworld. He is confronted once again by Samus, and despite being defeated, he survives the fight and is later cured of his corruption after Dark Samus' defeat later on. Between the "Prime" trilogy and "", the Space Pirates reorganize on Zebes and hatch another plan to clone and weaponize the Metroids, while Ridley gradually begins to regenerate from his past injuries, gradually shedding his cybernetics. In the remake of the second game, "", Ridley, in his semi-regenerated form of "Proteus Ridley", attacks Samus on SR388 to steal the last remaining Metroid. Samus and the baby Metroid work together to defeat Ridley.
Metroid (fictional species)
Metroids appear in almost all games in the "Metroid" series. One particular Metroid, the Baby Metroid that imprints on Samus Aran after she destroys the Metroid Queen in "", becomes an important character in later games. They also made an appearance in "Kirby's Dream Land 3", the "Kid Icarus" series (under the name "Komayto"), and in "Super Smash Bros. Brawl" and "Super Smash Bros. for Nintendo 3DS and Wii U".