Evil Tiga (イーヴィルティガ Īviru Tiga) is an Ultra that originally a good Ultra. Later due to evil host's heart, he become "Evil Tiga" and the main antagonist of the 44th episode of Ultraman Tiga, "The One Who Inherits the Shadows".
Dr. Keigo Masaki stole Spark Lens from Daigo after he founds out that Ultraman Tiga was Daigo Madoka to fused with warrior and become Evil Tiga. Evil Tiga flight to the city and destroyed them.
The GUTS tried to stop him, but he decided to destroy the fighter jet so they can't disturb him. Suddenly, his former companion named Guarde tried to stop his master from destruction. Because of Guarde, Evil Tiga can't take it and started to killed him.
While Guarde tried to stop him, but it didn't changed his master, Evil Tiga. After Daigo got Spark Lens back, he transformed into Ultraman Tiga to stop him. Later Evil Tiga killed Guarde, much to Tiga's rage and started to fight with him.
During the fight, their color timers begans to run lower and they started to finished themselves once and for all. After that, Tiga started to get tired and almost fell down, but Evil Tiga's energy almost runs out and started to fall down, which made Ultraman Tiga got his chance to destroyed him once and for all with modified Zepellion Ray.