Akuma

Akuma is one of the main characters in the Final Ninja series.

Background
Akuma used to be Takeshi's boss and sent him to destroy the corporation of the evil Maxwell Murlock. However, when Takeshi retired, Akuma somehow became evil. He sent his assasins after Takeshi. Takeshi defeated them all, but knew that he had to regain the alter ego: the Final Ninja.

Involvement
Now, Akuma is the main antagontist of Final Ninja and sends his robots Alpha and Zero after you. He also has cyber-guards, laser-guards and more to go after Takeshi.

Strategy
Akuma seems to go really weak once you defeat robot Zero (hinting that Akuma might be inside robot Zero controlling him.

Quotes
I thought robot Zero could defeat you. I was wrong.

Trivia
There is a street fighter named Akuma.

Akuma wears an eyepatch and smokes a cigar.