Rat

Rats are recurring enemies in the Legend of Zelda series. They are small, agile enemies that strike quickly; however, they are usually nimble and can be killed with one sword strike.

The Legend of Zelda: A Link to the Past
Rats are found in the Secret Passage below Hyrule Castle and in several other dark areas like grottos and dungeons. They are relatively weak, but move deceptively fast, making them a minor threat for an unwary Link.

The Legend of Zelda: The Wind Waker
Rats occasionally appear out from holes in walls, attempting to attack Link. They can damage him either by simply touching him or by throwing bombs. If a Rat happens to physically attack Link without the use of bombs, a certain amount of Rupees (15 to 40) fall out of Link's Wallet. The Rat will then attempt to take the Rupees back into their holes if Link does not quickly get them back. When killed, Rats usually dropped a yellow Rupee. Special rats can be found in the Windfall Island jail maze. These rats can drop Link out of the maze if he crawls onto one of their trapdoors.

Link can also sprinkle All-purpose Bait in front of a rat hole, prompting the Rat living inside to sell him various items as thanks for the snack. These items include Red and Blue Potions, Hyoi Pears and All-purpose Bait.

The Legend of Zelda: Four Swords Adventures
Rats are one of the few enemies that can cause Link to lose Force Gems if they hit him.

The Legend of Zelda: Twilight Princess
Rats are found in several different regions, particularly the Arbiter's Grounds and the Hyrule Castle Sewers. Rats can be usually found gnawing on skulls or corpses. When provoked, Rats attempt to attack Link. There is also another variety of Rat known as Ghoul Rats, which cling onto Link to hamper his movement. These Rats can only be seen and defeated with the heightened senses of Wolf Link.

The Legend of Zelda: Phantom Hourglass
Rats can be seen scurrying around various dungeons and caves, but are rarely seen outside. In the Mountain Passage on Mercay Island, a Rat can be seen running in and out of two connected holes carrying a Small Key. Link must use a block to seal the entrance to one of the holes, then kill the Rat to get the small key and advance into the next room.