You seen a vision of Silver Horn speaking with Nana, whom he had coerced into functioning as the Tianna Camp's systems operator by threatening to kill her and all the other prisoners if she did not cooperate. He makes good on this threat, as once Nana meets X's party and begins secretly aiding them, Silver Horn forcibly relocates her to the Aqua Coliseum so you confront him He turned to you "The weak ones have no choice... They should just obey the strong ones. Obey the Rebellion forces! The slimy vermin of the world... must bow down to our power!"