Nyeve

Nyeve (also known as Impostor Link and Self-Proclaimed Hero in the guide) is a character in The Legend of Zelda: Phantom Hourglass. He can be found in the northwest quadrant, sailing a ship that looks somewhat similar to the King of Red Lions, which he calls the Prince of Red Lions. His outfit is almost exactly like Link's, except with a small white ball at the end of the cap, a heart-shaped belt buckle, blue boots rather than brown boots and a garden tool for a weapon. He is a middle-aged man, with red hair that connects to his beard. His brother is Nyave, a member of the maritime defence force who sails the southwestern sea in the Traveler's Ship.

In the fashion of Orca, the player participates in a minigame with him. If Link can hit him (without actually hurting him) 100 times, the impostor will give Link a Heart Container. Additionally, if you play the game again, he will reward Link with different things. For example, anything between 100 and 199 will earn you Treasure, and anything above 200 will get you Ship Parts. This can be repeated whenever you want by simply talking to him. You don't have to leave and re-enter after each try.

Nyeve is very important in the trading sequence, as when you give him the Hero's New Clothes, he gives you a telescope. The telescope belongs to the Hoho in the bottom left corner of the ship in the Southwestern Sea. He also says he got the telescope from his sister as a joke, but that is really similar to what happened to Link in Windwaker

His and his brother's names are plays on the words "Naive" and "Knave", respectively.

Theory
-The weapon he uses could be a reference to the Triumph Forks from Wind Waker as it looks like a huge fork