Zant Masks are enemies from The Legend of Zelda: Twilight Princess. They are giant, flying replicas of Zant's mask found in the Palace of Twilight. Link can defeat them by simply attacking them with his sword, and he can stun them by deflecting their energy blasts back at them with the Shield Attack. After launching an energy ball, they will teleport to another location in the room. The main difficulty with this enemy is that they often hover in Shadow Crystal Fog, although the top of their "body" can be seen through the fog.
Zant Masks usually attack in groups of two or more and generally guard keys.