Gomess

Gomess is a mini-boss in the Stone Tower Temple, the fourth and final dungeon in The Legend of Zelda: Majora's Mask. Appearing only when the temple has been inverted, Gomess is a phantom-like vampire creature surrounded by a swarm of Bad Bats serving to protect a vulnerable crystalline orb on its chest. This orb is seemingly the source of its power, and if it is destroyed, Gomess will perish. It always carries around a scythe adorned with the skull of a Stalchild. After its defeat, a Treasure Chest appears, containing the dungeon's Big Key.

Battle
Gomess moves surprisingly slowly and can only be seen doing a quick dash just as it comes in to sweep its scythe across the floor. Gomess mainly attacks in this fashion, but can also twirl the scythe quickly enough to have it serve as a make-shift shield. If facing a foe who frequently attempts to outrun it, Gomess can also send in its swarm of Bad Bats to attack. However, this risk-taking strategy leaves its weak point wide-open to attack.

Strategy
In order to conquer Gomess, Link, as pointed out by Tatl, must first find a way to disperse the Bad Bats. Tatl more or less intentionally leaves a subtle clue when informing Link of his opponent. Link must "shed light" on Gomess with the help of a Light Arrow. With the help of said arrows, a direct hit will cause the Bad Bats to scatter and reveal Gomess weak point, giving Link a chance to strike at the crystal on its chest. Gomess can only take so many hits before the orb breaks and kills it off.

By moving quickly, perhaps with the help of the Bunny Hood, Link can keep a safe distance to Gomess and tempt it to release its swarm of bats. This method will also leave it open to attack, which may be necessary if Link runs out of Magic/Arrows.