Soul Calibur is the spirit sword created to combat Soul Edge. Algol, the king that once wielded Soul Edge and lost his son because of the demonic sword, vowed to create a holy sword from the purified shards of Soul Edge that would oppose the evil sword, being its equal in strength and opposite in intent. Algol enlisted the help of the greatest sage in the land, who used purified fragments of the cursed sword to forge a new spirit sword, to be known as "Soul Calibur". After many failed attempts, the holy sword was born when Algol sacrificed himself to complete the ritual. However, the sword that was created was far from good due to Algol's thirst for power, and it was extremely similar in nature to Soul Edge. Nonetheless, the tribe that was tasked with guarding the sword slowly purified it to the point that it could be considered a holy weapon, while keeping dormant the dark soul that rested within the sword. The guardians lived in seclusion, passing the sword from generation to generation in secret. Whenever a warrior vowed to take on Soul Edge on his own, Soul Calibur appeared to prevent the cursed sword from causing any more damage. Soul Calibur finally appeared, somehow transformed into a different shape.