Key of Union

The Key of Union is a powerful weapon that appears in the "Day of Judgment" saga of the Roach Chronicles. The weapon was created out of the light and dark sacred energy samples from the Aether by the four survivors at the Graveyard of the Ancients. The weapon would allow the four survivors access into the Aether, as well as restore the balance of light and darkness in the Aether, which would restore the rest of reality.

Trivia

 * Like the Harbinger, the design of the weapon originates from a keyblade in the game Kingdom Hearts.