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.
List of Mega Monster Battle characters
are an alien race that serves as the antagonist of "Ultra Galaxy Legend Gaiden". Debuting in episode 46 of "Ultra Seven", these aliens previously attempted in an invasion by using a mechanical knockoff of Ultra Seven before the real giant thwarted their plan. Stationing on Planet Chain, they created countless mechanical copies of the Ultra Brothers (save Taro and Mebius) in an attempt to invade the galaxy with the help of Darklops Zero, a prototype of Belial's Darklops army. Their first resistance appeared in the form of alternate reality versions of ZAP Spacy and the prime reality Ultraman Zero, before the prime reality Hyuuga and Rei appeared to assist them. Having stole the alternate Reimon's Battle Nizer, they used it in the creation of Mecha Gomora as an addition to their forces. However, Darklops Zero, whom was controlled and restrained by them, break free and rampaged, destroying their army as well as killing their leader, Herodia. was the antagonist faction that appeared in "Revenge of Belial". An invasion army formed by Ultraman Belial, now named as Kaiser Belial, the group's main base of operation is the .
 is the main antagonist of "Killer the Beatstar". Created by an unnamed alien race when the fearful Alien Bat had destroyed an entire universe, Beatstar's purpose was to control the planet-sized lifeboat, the to another universe but when his creators raged war with each others, he fully viewed organisms as evil creatures and resorted to build an army of robots in a plot to kill all lifeforms. His consist of reprogrammed/captured robot armies from past Ultra Series' antagonist, with the recent one being Jean-bot, whom was also used as the forerunner of his ultimate creation Jean-killer. However, the Ultimate Force Zero and ZAP Spacy destroyed his army, while Ultraman Zero and his defected creation, Jean-killer (renamed Jean-nine) destroyed him before he could destroy Planet Bram with his own sphere.