Ku

The  or Kuu is an aquatic cyclops enemy that acts as a Dark World counterpart to River Zora in A Link to the Past. Like River Zora, they pop up out of whirlpools to fire a single fireball at Link before disappearing under the water again, however unlike Zora they will never emerge fully from the water, so the shape of their body beyond their head is unknown. Also unlike Zora, they do not appear to have a king or leader of any kind, although they do share some similarities with the Big 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.

Trivia

 * Ku appear to have long, pointed ears, not unlike Hylians or Hinox.
 * In Four Swords Adventures, most River 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.