Ku

The Ku is a one-eyed aquatic enemy in and. It is the Dark World and Lorule counterpart of the Zora.

Characteristics
Like Zoras, Kus pop up out of whirlpools to fire a single fireball at Link before disappearing under the water again. Unlike Zoras, they do not appear to have a king or leader of any kind, although they do share some similarities with the Catfish that lives in the Lake of Ill Omen. Ku are common in the waters of the Dark World, with most appearing at the Lake of Ill Omen, the Ice Lake and even the Swamp of Evil where they share their home with Swamola. It is possible that they use Whirlpool Warps to travel around the Dark World much as the Zoras do, but there is only one of these warps in the Dark World.

A Link Between Worlds
Like most Dark World enemies, Kus reappear in A Link Between Worlds, this time as inhabitants of Lorule. In this game, they can also appear on land, revealing their full bodies. They have webbed feet and a turtle-like shell, causing them to resemble kappas, the famous aquatic demons of Japanese folklore. They will charge at Link, running swiftly on land. This type of Ku can be found in the Treacherous Tower and Ku's Domain, a large waterfall found in the northeast of Lorule where Kus gather. If Link defeats all the Kus at Ku's Domain, he will obtain a silver Rupee. The Kus in the Treacherous Tower appear in puffs of purple smoke.

Trivia

 * Ku appear to have long, pointed ears, not unlike Hylians or Hinox.
 * In Four Swords Adventures, most Zoras encountered throughout the game somewhat resemble Ku, having a single eye. These Zoras also live in swamps.
 * Ku are the subject of an infamous glitch in A Link to the Past, known as the Ghost of Misery Mire. It appears to be the result of Ku being placed in shallow water in the Swamp of Evil, perhaps because the developers had originally intended for them to leap from the water and attack on land much like the Zora at Zora's River, or because they had changed the layout of the shallow water in the swamp.