DethI

''""Nightmares shall never vanish, so long as I live."" ''

Dethl is the final boss of "Link's Awakening" and "A Link To The Past" and is the starter of bad dreams. His power is that he can enter anyones' mind and make them have nightmares until he has complete control over the one he has taken over. His main goal is to rule the world through making everyone have nightmares and lock them in those nightmares for eternity. By starting this plot he caught the Wind Fish, and locked him in a nightmare, which started to cause problems across all of Hyrule. So Link soon enough got caught by Dethl as well, locking him in a nightmare. Dethl knew Link had the triforce of courage and knew that Ganondorf had been defeated by him before (as it is noted that Dethl once transformed into Ganon), so he put as many traps as he could in Link's nightmare, which proved to be no match for Link. Then, Link attempted to face off against Dethl in which Dethl won and sent Link to the Wind Fish's nightmare where Link would trek all the way to Dethl's land and fight him in the final battle, freeing the Wind Fish and himself from Dethl's evil grasp. When Dethl is defeated he states that he can never be truly beaten, after that he vanishes and is believed to be somewhere else in the world.

Personality
Dethl is a power hungry, self-centered being that wishes to rule two worlds at the same time. By doing this he needed the Wind Fish asleep, in which he suceeded. Then he would spread the nightmare, showing that he has also planned everything out. He is also very violent, in which he tries to attack whenever he has the chance to do any pain to anyone or anything. His ruthlessness gives him an edge in battle making him harder to hit than most Zelda bosses.

Powers
Dethl can transform into anything he wants to, but when he tranforms it is only in a dark shadowy version of anything that he has changed into. When in the form that he has changed to he has all the powers that the character he has changed to has, he also enhances those moves making it pretty hard to stop because of such changes during the battles. His main form is just some gigantic eye that has two arm-like structures. With these powers he is considered the hardest boss of Zelda history.

Trivia

 * It is noted that Dethl is the first "one eyed boss" meaning that he was the first of many bosses to come that has one eye.
 * Dethl also tranforms into bosses that were being thought of around the time of his first appearance. Bosses after him that he tranformed into: Molgera, Giant ChuChu, Jalhalla, Ganon (Twilight Princess)