Hector the Reflector
Yellow Yoshi fighting the ghostly Hector.
Hector the Reflector is the third boss in Yoshi's Island DS. He is a strange, egg-shaped ghost that resides in a ghost-like fort, filled with Boos, possessed furniture and other supernatural creatures. His fight is unusual, taking into effect the full potential of each screen. When the fight begins, he is invisible on the top screen, but visible on the bottom screen. Yoshi can peek into the "mirror" on the bottom screen to find Hector. When he does, the player must throw eggs at him on the top. After each hit, Hector throws a flower pot at Yoshi. His Invisighouls also throw furniture at Yoshi. After six hits, he vanishes, making the next level playable.
His minions, the Invisighouls