Hephaestus was the Greek god of craftsmanship, particularly metal smithing.
Hephaestus was responsible for the armor of Wonder Woman and the Annihilator commissioned by his brother Ares. According to himself, he always includes some sort of weakness in everything he makes, so that no one or thing can get too powerful. He also remarked that he needs to let Diana's armor out a little since her mother who wore it first didn't have her build.
In Greek mythology, Hephaestus was the son of Zeus and Hera, though in many versions he was only Hera's son as she conceived him without help of anyone but herself. He is brother of Ares and the nephew of Hades. Hermes and Athena are Hephaestus' half-siblings.