Zen-aku

Zen-Aku is a fictional character from the Power Rangers universe, appearing in the television series Power Rangers: Wild Force. He was voiced by Dan Woren for some episodes, and later voiced by Lex Lang.

Zen-Aku was a Duke Org, cursed ages ago and imprisoned within a wolf mask. When Master Org defeated Animus, Merrick took it upon himself to defeat his evil. Knowing that he did not have enough power to defeat Master Org alone, he obtained the cursed wolf mask and used it to defeat Master Org. However he was soon corrupted by the mask's power and Zen-Aku took control of his body. At his request, Merrick's comrades sealed him into a stone-coffin in order to protect the world from Zen-Aku's power.

Centuries later, he was released by Nayzor to destroy the Wild Force Rangers of the present day. As Zen-Aku, he battled them on several occasions until the Power Rangers learned the truth and helped free him from the curse, with help from the Rhino and Armadillo Wild Zords.

Zen-Aku would later return when the original curse trapping him within the mask was cancelled as well. Zen-Aku attempted to kill Merrick and absorb him to regain the power he'd had when they were bonded together. Zen-Aku was seemingly destroyed by the Rangers.

In the finale, it is revealed that Zen-Aku survived and seeks redemption, just like Merrick. Together the Org and Merrick as they travel the world together.

Note: "Zen-Aku" literally means "good-evil" in Japanese.