|“||You idiot, this is your chance to beat him for good, and you're philosophizing about fairness? You'll never be the best with that kind of an attitude.||„|
|~ Dr. Klein|
Dr. Klein is one of the main villains from Red's storyline in SaGa Frontier.
Dr. Klein was once a respected scientist, and a colleague of Dr. Okonogi, Red's father. However, Dr. Klein decided to use his knowledge for evil, eventually becoming one of the leaders of the criminal organization Black X, developing their weapons and doing biological research. Okonogi starts investigating Klein in an attempt to stop his madness, but Klein sends Shuzer to kill him. Shuzer kills Dr. Okonogi and almost kills Red, but the hero Alkarl saves Red by turning him into the hero Alkaiser. Red uses his newfound powers to fight Black X, defeating their Four Emperors and making into Black X's base, where he confronts Dr. Klein. Klein sends his rebuilt Four Emperors to fight Alkaiser, but they are all defeated again. Boss X, the true leader of Black X, annoyed by Klein's successive failures shoves him away and decides to deal with Alkaiser for himself.