The 閻魔刀: Yamato (閻魔刀：大和, Enma Katana: Yamato?, lit. "Devil blade: Yamato") is Vergil's trademark dark-forged blade appearing in Devil May Cry, Devil May Cry 3, and Devil May Cry 4. It is a legendary sword that was once wielded by his father, and was left to Vergil as a keepsake. It resembles a Japanese Ōkatana, though it is said to be able to cut through anything as it is even sharper than an Ōkatana[4] and is imbued with tremendous magic. These qualities are important in its ability to both open and destroy the Hell Gates.
The Yamato once belonged to Vergil's father, Sparda, and according to the Order of the Sword, it was used to seal the "true Hell Gate". It was eventually given to Vergil as a memento, and he uses it as his primary weapon in Devil May Cry 3. It was somehow found, broken, by the Order of the Sword, and their act of taking it is what drives Dante to retrieve it by entering Fortuna in Devil May Cry 4. It is kept in Agnus's Containment Room within Fortuna Castle, but is restored and taken by Nero when his dormant powers as an heir to Sparda emerge. Thereafter, Nero is able to use the sword while in Devil Trigger. However, it is taken back from him by Sanctus when he is absorbed into the Savior, and is then used by Agnus to reopen the Hell Gate. After slaying Agnus, Dante retrieves the Yamato from the gate, which he destroys with it. Thereafter, he wields it while his Dark Slayer Style. While fighting the Savior, Dante uses it to free Nero, and gives it back to him. At the end of the game, Dante charges Nero with keeping it. It hasn't been revealed yet as to how Yamato was broken, or what happened to it after Vergil was corrupted and became Nelo Angelo.
