Yeah, I've got to agree with Joe there. The rest of the game doesn't match your Link sprite.
Anyway, more screenshots from my other custom boss. Kind of lame... I still haven't really figured out a good way to make them move around, so this one doesn't either.
The "Armos Knight," for lack of a non-generic name.
Shoot the magic sponges that protect him.
Then use your magic on the mirror to damage him. After two hits, he begins to jump and rocks fall.