The Century Cube is a standalone armor piece that can be obtained in the Nightmare. It can be purchased from Rising Waters in The Hidden Library at a price of 8,800,000 gold. Other viable methods of acquiring the Century Cube include but are not limited to:
- A possible reward from the Guttermouth Cells.
- A possible reward from The Lost boss.
- A possible serving served from The Deli's waits.
In appearance, the Century Cube is a cubic-shaped helmet with several square patterns on the sides and top of the mask. Each square-shaped plate appears to be made out of gold and other yellow gemstones/minerals. Two 'black eyes' can be seen on the front of the mask, as well as an open breathing hole (mouth) at the center of the mask.
Once equipped, the players will receive 15 armor points, slightly increasing their protection. They will also receive 80 additional points to all damage-types, increasing the number of damage inflicted on opponents while using any weapons.
- The Century Cube is one of the many items with the word 'Cube' in its name. Other examples include but are not limited to the Concentration Cube, Clever Cube, and Freedom Cube.
- The Century Cube is one of three "cube" headpieces that provides increasing amounts of armor and all damage types. The other two cubes are the Kitchen Cube and the Clever Cube.
- The Century Cube's description mentions a planet known as Earth, however, it is unclear whether or not it is referring to the real-life planet that we live on, or to another planet that exists in the universe of Fantastic Frontier.
- It may be affiliated with The Object From Earth.