Monster 1 is the first monster to be encountered in the Karamari Hospital DLC.
Monster 1 wears a blood-soaked police officer/security guard outfit, a black necktie, and black shoes. His eyes are black and with a dark discoloration around the sockets and he seems to be lacking a mouth. His most prominent feature is his arms, which are hideously swollen from the elbows down with no visible hands or fingers.
Monster 1 appears past the sealed doorway after the power has been turned off. At first, he stands motionlessly, blocking the stairway, however, he will start to move towards the player if they enter one of the side rooms and re-enter the main hallway.
When he gets close to the player, he will pause for a moment, before rapidly moving towards them. If the player is hit by this, they will lose about 1/4 of their health.
Swinging the Sword at him three times will successfully kill him. He will not respawn even if the player leaves and re-enters the room.
"Bleh Wind," Monster 1's chase theme.
- When he is standing in front of the stairway, he will not damage the player even if touched.
- He and Monster 3 are the only enemies from the DLC to have animated models.
- He and Monster 7 are the only monsters from the DLC not to be included in Endless Mode.