In Metal Gear Solid, Psycho Mantis is the boss who uses psychic powers and reads the player’s memory card.
Psycho Mantis is a member of FOXHOUND and the fourth major boss encountered by Solid Snake. His battle is famous for breaking the fourth wall: he comments on the player’s actions and appears to anticipate Snake’s movements.
On the original PlayStation, the game instructs players to move the controller to controller port two, making Mantis unable to read Snake’s movements. He also comments on save data from other Konami games. The encounter is often remembered as one of the series’ clearest examples of interactive storytelling.
Psycho Mantis is not the same character as Decoy Octopus, who impersonates the DARPA Chief. His distinctive gas mask and telekinetic abilities are central to the boss fight.