Illidan

A character in the Warcraft series. Illidan as an anti-hero was the first Demon Hunter. A decision he made during the War of The Ancients where he and other people like him would take on some of the power of the demons in order to fight them. A decision that was highly opposed by most of his people, but especially his brother Malfurion and his wife Tyrande Whisperwind. Illidan's addiction to magic and power would continue to put him at odds with his people to the point that his brother had him jailed for ten thousand years. Being looked over by Maiev Shadowsong and her wardens.

During Warcraft III: Reign of Chaos Tyrande helps Illidan escape hoping that he can help with the fight against the demons and Archimonde specifically. Illidan decides to help by consuming the skull of Gul'dan. A demonic artifact that gives him the ability to enter an enhanced demonic form. Which he uses to save Felwood by killing Tichondrius. Tyrande and Malfurion are not happy about Illidan's new demon powers and he flees the scene.

During the events of Warcraft III: The Frozen Throne. Illidan starts off the expansion by raising the Naga led by Lady Vashj from the sea floor. Him and his new found allies are being chased by Maiev who wished to imprison Illidan again for his previous crimes and for killing her wardens. Illidan gained knowledge from the Skull of Gul'dan that told him about the Tomb of Sargeras. Maiev chases him through the tomb and despite her best efforts he manages to get an artifact called the Eye of Sargeras. Illidan wants to use the eye to destroy the The Lich King and his Frozen Throne. The reason he wants to do that is because a demon named Kil'jaeden demanded he do so or face his wraith. Maeiv convinces Malfurion and Tyrande to get involved with the chase against Illidan only through a strange series of circumstances do they realize she is crazy and despite Illidan working for a demon what he wanted to do was actually "good" for the world. They don't realize this before destroying the eye, but Illidan and his brother leave on good terms for the first time in thousands of years.

After the failure of his plan with the eye. Illidan is now being chased by both Maiev and Kil'jaeden. He decides the best course of action for him and the Naga is to flee Azeroth by going to Outland. On the way to make this happen, they meet the prince of the Blood Elves Kael'thas and by helping him flee some racist humans under the provisional command of Othmar Garithos and promising to help his peoples magic addiction they become allies to Illidan and the Naga. Together they all make their way to Outland, finding his last big group of allies a legion of broken Draenei led by Akama. They all band together and defeat the current leader of Outland Magtheridon. The group doesn't have long to feel victorious when Kil'jaeden appears and demands that Illidan and his new allies finish the job he gave him of destroying the Lich King.

Illidan and his allies make their way to Ice Crown in Northrend to destroy the Lich King, but Arthas Menethil and Anub'arak thwart their attempts to reach the Frozen Throne, with the ultimate outcome of the expansion being that Arthas defeats Illidan and claims the Frozen Throne and the title of Lich King for himself.

Illidan and his allies return to the Outlands after their defeat and remain there until the events of World of Warcraft: The Burning Crusade where they are systematically defeated by players and their respective factions. Illidan himself is defeated by players aided by Akama and Maiev.

Illidan didn't "die" when he was defeated, but since he was sufficiently demonic his soul went to the Twisting Nether. During the events of World of Warcraft: Legion he returns to help players and their allies defeat a Burning Legion invasion. The conclusion of the expansion is that Illidan helps players defeat Argus and ironically he becomes the jailer of Sargeras.