"J. K. Rowling once joked that the Squid is Godric Gryffindor, one of the four founders of Hogwarts. This would make it the world's largest Animagus. On the eleventh hour of every evening, the Squid would rise from the lake and transform into Gryffindor, who would wander the school grounds before returning at sunrise. She was unexpectedly taken seriously by many fans, before she was forced to clarify this was actually a joke."
https://harrypotter.fandom.com/wiki/Hogwarts_Giant_Squid
https://harrypotter.fandom.com/wiki/Hogwarts_Giant_Squid