Nico's Sword

Nico's sword is a black sword forged from Stygian iron. Nico acquired it at some point between The Titan's Curse and The Battle of the Labyrinth. The sword's origin is currently unknown, but there is a possibility, that Nico forged it in The Battle of the Labyrinth when he is seen in a camp ground near the River Styx. The sword has the power to suck away it's victim's essence. Percy describes it as being "black as a nightmare and truly frightening."

Uses

 * Nico uses it to summon the dead by stabbing it into the ground.
 * He can also banish the dead by stabbing the sword into the ground.
 * The dead are scared of the sword and shy away from it.
 * The swords sucks the essence of the killed monster into the sword.