Planar Blade of True Striking
From D&D Wiki
Enhancement: +20 to hit, +10 to damage
The Planar Blade of True Striking was created in a joint effort by the mage Elminster and the red dragon Alexstrazza, before dragons were affected by the Rage. It was forged using a mix of dragon fire and Spellfire, in multiple pieces on multiple planes. Each individual piece was forged using dragonfire. The blade was comprised of four pieces, one each being made on the Astral Plane, the Fey wild, the Shadow Rift, and Arcadia. The pommel was created in two pieces, one being made on the plane of Mechanus, the other on Pandemonium. The crossguard is forged of one piece created in the abyss. The creators took these pieces, all crafted in good, evil, neutral, lawful, and chaotic realms to an unknown location in Ferun and fused together with Spellfire. The joining of the pieces made a sword that is both beautiful and horrible to look upon.
Upon completion of the completion of the Planar Blade of True Striking, it was given to an unknown warrior, who used it through his career. The last known information on the sword is that it was taken by the demon who killed the warrior.