Believer

A character with black hair and blue eyes stares intensely, followed by a close-up of a character with dark hair and red eyes looking shocked as blood splatters on a blade, then a character with white hair and a determined expression, next a character with dark hair and red eyes restrained by red tendrils in a dark alley, then a bright blue light effect, and finally a close-up of hands gripping a weapon in a dark environment.