Dowser

Dowser is a dog that appears in The Shadow Prince. He is first introduced after Link, Princess Zelda, and Charles of Moria arrive to North Castle for the first time. Dowser comes in to interrupt the Charles in the banquet hall and licks both Link's and Zelda's face; however, when he sees Charles, he growls at him. Afterward, he lunges for Charles's throat, but Zelda holds him back. Dowser's sudden action makes Link wonder why Dowser, who is always nice to new people, does not like Charles.

The book then offers a puzzle to give the reader a hint on what upset Dowser. When the puzzle is completed, it spells out the word "NECK," implying that the dog disliked Charles's necklace. Sure enough, it is later discovered that Charles is actually Ganon, and the necklace is what gives him power.