Master Sliver

Sliver is a villain from the Teenage Mutant Ninja Turtles franchise, a dark and corrupted counterpart of Master Splinter who is as ruthless and cruel as his mainstream self is kind and wise.

Born to another universe Sliver wanted to destroy humanity and turn his students into monsters like himself - which in some ways makes him comparable to the Shredder of the main world (especially the Utrom Shredder).