|Name:||Terios the Hedgehog|
In Betrayal of a Hero, Terios is a member of the first generation of Freedom Fighters. One day, he is wounded in the shoulder during a shootout against G.U.N. in Acorn. During his unconsciousness, he meets Mephiles the Dark, who persuades Terios into joining his cause, by giving him the Phantom Ruby to destroy G.U.N. After Terios awakens, he rests outside for the night, joined by Tangle the Lemur, his love interest. That night, he is revisited by Mephiles, who warns him that he will transform into a Phantom in the coming days. He then leaves Acorn for Mobotropolis, unknowingly followed by Tangle. Upon arriving in Mobotropolis, Terios proceeds to use the Phantom Ruby to become the Phantom Zero, who then destroys the G.U.N. headquarters. He returns to the city, to find Tangle weakened by Mephiles. After she dies in his arms, Mephiles seals the deal by telling Terios that G.U.N. killed her. Terios then promises revenge on the government.
Terios is a kind-hearted, strong warrior, while blunt all the same, blocking out what's around him in times of agony. His personality becomes irrelevant when transforming into Zero, however, during which he becomes a mindless killing machine.