Destoroyah is the main antagonist of Godzilla vs. Destoroyah and stands out as one of Godzilla's most destructive and powerful enemies. Starting out as a colony of precambrian crustaceans mutated by the Oxygen Destroyer, the beasts later fused together and evolved into an abomination.
Destoroyah's origin lies in the detonation of the Oxygen Destroyer, the device used to kill the original Godzilla. During the detonation, the device mutated and revived a colony of crustaceans. Many years later, the creatures were released by an underwater drill and spread into an aquarium and killed off the fish and evolved into human-sized beasts that ran lose on Japan and hid in a factory. The Japan Self-Defense Force were called in to deal with the monsters. This was a one-sided battle, The crustaceans clearly more powerful and used their abilities to attack the Defense Force. The JSDF were losing until flamethrowers were brought in, driving the monsters away. As the monsters left, one of the juveniles came back and attacked the unprepared group, and nearly killed a reporter until the flamethrowers were able to kill it. Realizing the juveniles were vulnerable to extreme temperatures, and they brought in maser tanks to arradicate them. Realizing they couldn't win the battle, the juveniles fused together and evolved into a giant aggregate form that looked like the juveniles but was much larger and equipped with long, insect-like legs and crab-like claws. Now strong enough to withstand the maser tanks beams, the monster caused massive destruction and morphed into a flying monster that flew over the city, sending down destructive beams that detsroyed whatever it touched.
With little options, the JSDF decided to bring Godzilla, who was going through a nuclear meltdown that would destroy the world. Figuring that if the two fought each other, they would both kill each other and both threats would be destroyed. Two psychics lured Godzilla's son Junior to Destoroyah, who attacked and easily battered Junior until the young monster hit Destoroyah with an atomic blast. The beast them morphed back into its aggregate form that tackled Junior and injected him with micro-oxygen, causing him to foam at the mouth. Junior mustered up enough strength to blast Destoroyah into a factory. Godzilla finally arrived and reunited with his son. The reunion was cut short when Destoroyah returned. The monster had evolved again, and was now towering over Godzilla himself. The beast, now with four wings, flew to the mutated Godzillasaurs and brought Godzilla down with several blats from his micro-oxygen beam. Wanting revenge on Junior, the beast flew Junior into the air and dropped him onto the group and hit him with a micro-oxygen ray, killing him. Furious at Junior's death, Godzilla charged at Destoroyah, who accepted the challenge. A massive and destructive brawl ensued, and Destoroyah gained the upper-hand and nearly succeeded at killing Godzilla. But, fueled by the rage of Junior's death, Godzilla brutally attacked Destoroyah and brought the abomination to the ground with a red spiral ray. Refusing to admit defeat, the beast separated into smaller aggregate forms that ganged up on Godzilla, but they were destroyed by a nuclear pulse. With Destoroyah gone, Godzilla tried to revive his son, but failed. He failed to notice Destoroyah sneak behind him and attack again, throwing him away from his son. Now at the peak of his rage, Godzilla blasted Destoroyah apart with his red spiral ray, and caused Destoroyah to flee. The maser tanks then hit Destoroyah with their beams, and froze his wings, causing him to fall to the ground and explode.