Chain Chomp

The Chain Chomp is an enemy from the Mario series that also makes an appearance in a few Zelda titles. It is found as an enemy in A Link To The Past, as a friendly animals in Link's Awakening, and as both an ally and enemy in Four Swords.

A Link to the Past
In A Link to the Past, Chain Chomps can be found as enemies in Turtle Rock and the Palace of the Four Sword. They are invulnerable to all forms of attack and yield an incredible amount of damage. In Turtle Rock, there are only two Chain Chomps found in one room.

Link's Awakening
In Link's Awakening, Chain Chomps are docile animals; three of them are kept as pets by Madam MeowMeow in Mabe Village. Her most beloved Chain Chomp, tied to a post just outside the door, is named BowWow. After completing the Tail Cave dungeon, BowWow is kidnapped by a gang of Moblins. Link rescues him and brings him back to Madam MeowMeow, who then asks Link to take her pet on a walk. BowWow can then be used to eat the otherwise-impenetrable Goponga Flowers blocking the entrance to the game's second dungeon, Bottle Grotto. Although BowWow can take care of most enemies for Link, he cannot be taken into dungeons. After Link completes Bottle Grotto, he must return BowWow to his owner.

Two more pet Chain Chomps are owned by Madam MeowMeow. A smaller one is inside her house and a second is in a doghouse nearby. The second Chain Chomp is quite obviously a female, with a strong desire for jewelry and other such accessories. She helps Link with the trading sequence: if Link gives her the Ribbon, she will give him the Can of Dog Food.

In Link's Awakening DX, a picture can be taken with BowWow.

Four Swords
A Chain Chomp can be obtained as an "item" in Vaati's Palace. While the Chain Chomp is the "pet" of one of the Links, it attacks enemies and other Links within its reach. Like all items in an area, the Chain Chomp is not a permanent item.

In the 25th Anniversary remake for the Nintendo DSi and 3DS, a Chain Chomp can be found in the Realm of Memories during the Goponga Swamp section of the area based on Link's Awakening. It is required to finish a puzzle involving an otherwise unreachable enemy.

Four Swords Adventures
A Chain Chomp appears again, briefly, as an indestructible obstacle in Kakariko Village. As with Link to the Past, this one is an enemy in the same sense Blade Traps are enemies.

Trivia

 * In the original version of Four Swords, the Chain Chomp was also named "BowWow". This was changed in the anniversary edition.