Hephaestus is the secondborn son of Zeus and he is the Greek God of fire and blacksmiths, appearing in the Soul series of fighting games. Hephaestus feels that Soul Edge, a weapon made by man, is so powerful that if all of the shards were allowed to assemble, the resulting sword could stain his reputation as the greatest blacksmith in the universe. Because of this fear he sends oracles to 24 people to go and destroy the evil blade. Among them was the Spartan warrior, Aeon Calcos and Sophitia Alexandra, the civilian daughter of a baker. Aeon Calcos never reached the sword, but Sophitia was able to shatter one of the blades. Ever since Soulcalibur II, Sophitia's younger sister Cassandra Alexandra blames Hephaestus for putting such a great burden on Sophitia. In Soulcalibur III, Aeon Calcos, now as a lizardman, searches for Soul Edge to have his revenge on Hephaestus, for abandoning him to live as a monster. Hephaestus' greatest fear is that Soul Edge could fall into the hands of his older brother, Ares, the God of War.
Hephaestus has given out new oracles and a new set of sacred warriors has been born. They have a secondary objective besides the destruction of Soul Edge, fight the "beast who devours people".
- Sent twenty-four warriors to destroy Soul Edge, including Sophitia and Aeon Calcos.
- Blamed by Cassandra to put a heavy burden in Sophitia.
- Also blamed by Aeon himself for leading the latter into an awful fate which permanently stuck in his Lizardman form.
- The Colossus from Soulcalibur III has his shape.
- Enemy of Ares in Soulcalibur V.
- In Soulcalibur III, the player can fight a Colossus with Hephaestus' shape in the Tales of Souls and Soul Arena.
- Hephaestus appears in Sophitia's endings on Soul Blade. He helps her destroy Soul Edge by sending a thunderbolt into the blade, shattering it. He then tells her about how powerful it is.
- He is voiced by Jin Yamanoi in Japanese and Robert Belgrade in English in his appearance in Sophitia's ending.
- It is possible that all the weapons that Hephaestus gives are named after Greek letters. Sophitia's sword is named Omega, and Aeon's was originally called Xi.