Agahnim

Agahnim is the dark wizard who serves as one of the primary antagonists in the game The Legend of Zelda: A Link to the Past.

It is commonly believed that Agahanaim is merely a disguise of Ganon and not a seperate being.

Biography
When the land of Hyrule became besieged by an onslaught of terrible misfortunes, like pestilence and drought, the King of Hyrule offered a reward to a person who could put an end to these problems. A mysterious man named Agahnim came and put an end to the troubles with a previously unknown magic. He was declared a hero and was given the positions of Chief Advisor to the King, Priest, and Heir to the Seven Sages. Agahnim used this position and his mysterious magic to brainwash all of Hyrule's soldiers, make the King of Hyrule disappear, and capture six of the descendants of the Seven Sages to make them disappear to the Dark World.

After Link rescued her, Zelda hides in the Sanctuary. She was the last of the descendants, so Agahnim would probably come after her as well. Eventually, Agahnim's troops find her and take her to the top of the highest tower of Hyrule Castle. Agahnim then sends Princess Zelda to the Dark World, this breaking the seal of the Seven Sages. He tells Link that nothing can stop him now, because his men are now armed with the Triforce, and that evil and darkness will soon overrun the Light World. He then vanishes, but Link manages to find him in an hidden chamber where he duels the Dark Wizard. Before Link can defeat the wizard, he flees into the Dark World. During Link's quest to rescue the seven maidens, Link learns that Agahnim is a servant of Ganon.

When Link defeats Agahnim a second time, at the top of Ganon's Tower in the Dark World, Agahnim collapses, and from his body a faint image of Ganon appears. This image turns into a bat and flees to the Pyramid of Power. At the start of the final battle, Ganon reveals that Agahnim was in fact his alter ego.

Strategy
Link can't hurt Agahnim directly, not even with the Master Sword. Link must use his own magic attacks against him. When attacking, Agahnim hurls magic attacks at Link. The first one is a magic ball, which can be hit with the Master Sword to reflect it, and make it wound Agahnim. the second attack can also be hit with the Master Sword, but it splits up in multiple fireballs flying through the room. The third attack is a lightning attack which Link can only avoid by standing at Agahnim's side. The lightning strike cannot be reflected. If Link strikes at Agahnim directly, he receives a electical shock.

While he fights alone in Hyrule Castle, in Ganon's Tower, he creates clones of himself to confuse Link. This can actually work to Link's advantage, as the clones create magic balls that can be bounced back.