Mother Dorrie

Mother Dorrie is a bizarre foe encountered in Super Mario 64 in the Hazy Maze Cave stage that is presumably manifested as a result of the Personalisation A.I. which is found in the depths of the cave, where one typically finds Dorrie, the blue plesiosaur. This version of Dorrie is extremely fast and hostile, and will swiftly attack any player who encounters it. Some reports also suggested that it can appear in Salty, Salty Shore.

Overview
Mother Dorrie's skin is black, with a white belly pattern similar to Dorrie, but differs from aforementioned by the very noticable sharp, long orange and red teeth. Mother Dorrie, unlike its original counterpart, is very aggressive. She will try to chase the player at extremely fast speeds in the pond and will kill them instantly if she catches them, resulting in either a game over (regardless of how many lives the player may have remaining) or the game freezing. Mother Dorrie also has dark fluids, likely saliva, dripping from their mouth. They also have very small, hard to notice, black eyes.

The conditions required to spawn Mother Dorrie are currently unknown, and is potentially random.

"Don't become his lunch"
The Hazy Maze Cave sign near Dorrie said: “''A gentle sea dragon lives here. Pound on his back to make him lower his head. Don't become his lunch.''”. This sign does not refer to Dorrie, as Dorrie is entirely harmless to the player, so it is very possible the sign is referring to Mother Dorrie. It is unknown why the sign is present in all copies of the game, while Mother Dorrie is not.