X-Naut Fortress

The X-Naut Fortress (Japanese メガバッテンのアジト Megabatten no Ajito) is Grodus' main base of operations which is located on the Moon and the home to the X-Naut Legion in Paper Mario: The Thousand-Year Door. This place is also where Princess Peach was taken to. The last Crystal Star, the Crystal Star, is held there and Mario and his friends had to use the cannon in Fahr Outpost to reach this place and fight Lord Crump (while driving Magnus 2.0) to get the Star. Grodus got to earth and back to his fortress using a Teleportation Machine, which has one end located in his laboratories and the other end located in Rogueport Sewers. The base is also the home of TEC-XX.

The fortress is essentially a four-story building built deep under the Moon. It's all connected by a series of hallways and two elevators. The deeper Mario or Peach go, the dimmer the lighting is.

Enemies

 * Elite X-Naut
 * Magnus Von Grapple 2.0 (Chapter 7 Boss)
 * Mini-X-Yux
 * Mini-Yux
 * Mini-Z-Yux
 * X-Naut PhD
 * X-Naut
 * X-Yux
 * Yux
 * Z-Yux

Trivia

 * When the player spring jumps into the air duct from the Yux lab on Subfloor 2 and use Paper Mode to slip thought the vent on the far right, you will land in a changing stall in an adjacent room. Pull the curtain back and Mario and his partners will be 8-bit sprites. This lasts until you leave the room.
 * Grodus' room contains a tank filled with Nibbles. This is the only place you can see their entire body.