Destoroyah

the baddest nemesis aside from king ghidorah. Destoroyah was born when the oxygen destroyer from Godzilla 1954, infected a bunch of crustaceans originating from the Cambrian, pissing them off and allowing them to progressively get bigger and meaner the more they combined until they became Satan itself and killed Godzilla junior, only to be whooped by Godzilla and frozen by the jsdf, killing the creature in its entirety.

Destoroyah's abilities include the oxygen ray "a purple death laser that hurt the big G himself", a samurai sword horn "which could make swiss cheese out of anything that it touched", energy absorbing "where it stabbed stuff with its tail and got stronger ",and changing changing forms "allowing it to change from a shrimp, to a demon crab, to a bigger demon crab with spears, to a legless flying red bat with the perfect forms face, to a big satanic knock off that made the main characters shit themselves."

its on screen appearance was in the 1995 film, Godzilla vs Destoroyah, the kid series Godzilla island where it was an action figure, and it has made numerous comic appearances including Godzilla rulers of earth, Godzilla legends "where Anguirus of all things made it its bitch", Godzilla cataclysm ,and Godzilla in hell.