Vire

The Vire is a bat-like demon that appears in The Legend of Zelda, Link's Awakening, Oracle of Ages and Oracle of Seasons, as an entity made up of Keese. The Vire tends to live in areas of darkness, like its Keese relatives, and even tends to split into Keese when injured, although Link can dispel this enemy by using a strong weapon, like the Magical Sword or the Fire Rod.

The Legend of Zelda
First encountered in The Legend of Zelda, Vires are large, blue devils. encountered only in labyrinths. When harmed, they split into two red-colored Keese, which float around the room like regular Keese. After dispatching the red Keese, if Link exits and immediately returns to a room, the Vires will all be back, since they haven't truly been killed. If it is hurt by the arrow, Magical Sword, or any weapon which does at least four damage, it will instead die.

Link's Awakening
In Link's Awakening these rare and fast flying creatures appear in only the hottest of dungeons, swooping down at random to try and harm Link. They fly around shooting Fireballs, which can be blocked with a Sword swipe, and after three or four of them, will swoop down at Link. Three blows will take it out, and cause it to explode into two Big Keese. The easiest way to defeat these monsters is to use Link's Hookshot. A zap from the Magic Rod kills it without causing it to split.

Oracle of Ages and Oracle of Seasons
Appearing in both Game Boy Color titles: Oracle of Seasons and Oracle of Ages, this red bat plays the role of henchman to both Veran (Oracle of Ages) and Onox (Oracle of Seasons). Depending on which game is played first, Vire will begin as an underling of the villain Link is currently up against. Vire also appears at various points during Linked Games to cause various trouble. In both games he is the miniboss in the sixth dungeon (Ancient Ruins/Mermaid's Cave). He will fly around evading Link and firing energy balls at him. After hitting him several times he will split into two smaller bats and they will try to tackle Link, one swipe of Link's sword takes both of those bats down.

Animated series
Vires appear in three episodes of the animated series. In "Sing for the Unicorn", when Link confronts Ganon and demands that he let King Harkinian free, the Vires that were accompanying the evil wizard begin to attack the young hero. Link zaps a few with his sword until three of them grab him and lift him into the air, allowing Ganon to escape on a Unicorn with the king. Link eventually manages to free himself from the Vires and goes after Ganon by grabbing onto the Unicorn's tail, but the evil wizard zaps Link, causing him to lose his grip and begins to fall to his death. However, Link manages to survive the fall partially due to him grabbing onto the feet of Vires that were on his way down.

In "Underworld Connections", three Vires fly towards the chamber where the Triforce of Wisdom is being kept and place a bomb near the sacred relic. Zelda realizes that they plan to blow up the Triforce with a bomb so that they will be able to carry it back to the Underworld. Although Link rushes over to stop the monsters, he is knocked over by the explosion of the bomb and is rescued just in time by Zelda. The young duo make it in time to zap one of the Vires carrying a shard of the Triforce, but the other two manage to get away into the Underworld. Thinking quickly, Zelda remembers that, since all of the pieces of the Triforce are magically linked, if Link shoots a sword beam into the shard that they currently have, it will go through the two others and zap the Vires. The two Vires are effectively defeated, but due to the foes taking separate ways to the Underworld, one of the pieces falls into the Black Falls and another one into a lava area.

In their final appearance in "The Moblins are Revolting", the Vires are part of the Brotherhood of Underworld Monsters and are one of the many foes who try to get revenge on Link and Zelda. In one particular scene, a Goriya orders several Vires to carry Octoroks so that they can fly above the North Castle walls and bomb the inside.

Trivia

 * Its name, "Vire", may be a contraction of the word "Vampire."
 * Gomess is another entity made up of Keese-like creatures, the Bad Bats, that appears in Majora's Mask.