sentences:  Like Sora, Roxas has the power to wield the Keyblade, a weapon normally used for battling darkness.At the start of the game, Roxas joins Organization XIII, a group of powerful Nobodies who serve as the antagonists of "" and "Kingdom Hearts II".The other members of Organization XIII play a prominent role, particularly Axel, Roxas's best friend who debuted in "Chain of Memories".