Bubble

The Bubble is an animated skull with fire surrounding it, seeking out prey for its master. The main purpose of the Bubble is to induce fear in their victim by touch, leaving the victim trembling and unable to wield or use a weapon/item for a brief period of time. This leaves the victim open to attack from any nearby enemies and monsters. Link found these enemies virtually indestructible in his quests. They first appeared in the original The Legend of Zelda and have appeared in numerous games since then.

It is important to note that the Bubbles seen in the 3D Zelda games (i.e Red Bubble, Blue Bubble) have little in common with this Bubble other than similarity in appearance. Their attack patterns do damage and are completely different in many regards. In Ocarina of Time, they became a more diverse race, containing White, Green, Blue, and Red Bubbles.

In The Adventure of Link, a larger version can also be found.

In Twilight Princess, White Bubbles return simply being called "Bubbles" and bearing no flames. But there is another type of Bubble that does, called the Fire Bubble, which appears in certain dungeons. There are also Ice Bubbles, which freeze Link (but appear very rarely).

In Phantom Hourglass, there are Fire and Ice Bubbles. Both are easily defeated by stunning them with the Boomerang, then attacking them with a Sword, Bomb or Bombchu. Sword is most suggested, as the latters are too time-consuming. They can also be destroyed instantly by a single arrow, though are fairly hard to hit.

Trivia

 * A similar creature named Bonehead appears in the N64 Game Kirby 64: The Crystal Shards. Both monsters share a few notable similarities including having wings and growing the wings when it is approached.