He-Man and the Masters of the Universe (1983)

Season 2: Episode 63

An alien race called the Vendari, which knows no evil, visits Eternia, wishing to see the difference between good and evil for themselves, and which side is stronger. They select Fisto from the side of good and Spikor from the side of evil, to compete against one another in a series of games. However, Fisto's chances of victory are threatened by Skeletor and his crew, who refuse to play fair and do all they can to ensure Spikor emerges victorious.