The Third Eye on the back of Daisy's Trophy head.
Daisy's Third Eye is a bug on Super Smash Bros. Melee which can be found on the Daisy trophy, right on the Trophies section of the main menu.
In the Japanese and early American versions of Super Smash Bros. Melee, positioning the camera through the hair in the back of the Daisy trophy reveals a third eye which looks completely different from her other two. This was fixed in the North American "Player's Choice" versions.