Area 51, a massive underground research facility housing various monsters, has been breached, and the creatures have escaped.

<Structure of Area 51> 1.) 1st Floor Facilities Access Corridor: The hallway at the entrance of the lab. You must pass through here to reach other locations. Robot Zone: Contains robots and mechanical monsters. Creepypasta Zone: Contains various urban legend monsters. Main Hall: The largest hall in Area 51. Connects to the 2nd floor and the sewers.

※ The entrance leads directly to the Access Corridor. At the end of the corridor, the path splits three ways. Left is the Robot Zone. Right is the Creepypasta Zone. Straight ahead is the Main Hall. The Main Hall contains stairs leading to the 2nd floor and the basement. You must pass through the Subway Station to reach the Sewers.

2.) 2nd Floor Facilities Prison: Inhabited by several Prisoner Zombies and one Guard Zombie. Factory: Located next to the Prison. Filled with countless conveyor belts. The only area without monsters.

3.) Basement Facilities Subway Station: A subway station within the facility, currently completely shut down. Serves as a corridor to the Sewers. Sewers: A dangerous area with narrow spaces and many rooms.

[Robot Zone Monsters]

1. Droid: Fodder, weak.
2. Guardian: A robot with a shield, fodder. Weak.
3. TV Head: Wears a white suit with a TV for a head, weak.
4. Big Eye: Large red eyeball head, wears a black suit, weak.

[Creepypasta Zone Monsters]

1. Jeff the Killer: A killer with a slit mouth, weak.
2. Evil Spirit: A black ghost, weak.
3. Friend: A one-eyed creature with blue hair, somewhat strong.
4. Vanta: A translucent red humanoid monster, uses psychokinesis, somewhat strong.
5. Frost Woman: A female monster surrounded by cold air, weak.
6. Slender Man: A faceless, tall figure in a suit with tentacles on his back. Somewhat strong.

[Main Hall Monsters]

1. Fedora Gentleman: Uses claws as weapons, weak.
2. Zombie: The weakest of the fodder. Weak.
3. Mannequin: Usually a mannequin, but suddenly moves to attack. Weak.
4. Glitch: A monster covered in noise. Strong.

[Subway Station Monsters]

1. Pale: A massive quadrupedal humanoid monster, somewhat strong.

[Sewers Monsters]

1. Zombie: Weak.
2. Three Heads: A humanoid monster with three heads, somewhat strong.

[Prison Monsters]

1. Prisoner Zombie: Stronger than a regular zombie, but still weak.

Boss Monsters: Monsters far stronger than the others.

1. Cyborg: Boss of the Robot Zone. The weakest boss, can be defeated easily.
2. Reaper: Boss of the Creepypasta Zone. The strongest boss.
3. Guard Zombie: Boss of the Prison.
4. Jack-o'-Lantern: Boss of the Sewers.