Things You'll Need
Instructions
Pause the game when the battle begins.
Unplug your controller from controller port 1.
Plug the controller into controller port 2. If you are playing on a PS3, assign the controller to port 2 in the PS button menu. This will prevent Psycho Mantis from reading your mind and anticipating your attacks.
Follow Psycho Mantis as he flies around the room. Punch him or shoot him with your SOCOM whenever he stops moving. Crouch to avoid damage from the flying furniture.
Punch Meryl to knock her out when Psycho Mantis takes control of her. Alternatively, you can also knock her out with a Stun Grenade.
Put on your Thermal Goggles when Psycho Mantis becomes invisible. Continue punching or shooting him until he is defeated.