Hephaestus's History
Pre-God of War
Before his elder brother Ares' death, and Kratos opening Pandora's Box, Hephaestus was the most prized craftsman of all Olympus, and was rewarded with marriage to Aphrodite. Hephaestus' deformed appearance may be due to being brutally attacked by Zeus after the King of the Gods was filled with the Evil Fear, and became enraged with Kratos' retrieval of the Box.
God of War: Chains of Olympus
Hephaestus was mentioned as the creator of the Gauntlet of Zeus. It is said in the description of the item that Zeus demanded him to craft a weapon that would bind the Titans to the very walls of Tartarus. Thus was created the Gauntlet of Zeus.
God of War III
First Encounter
When Kratos traveled through the underworld after being dislodged from Gaia, he stumbled upon Hephaestus in his forge. After exchanging insults, Hephaestus revealed that although Zeus was the one to imprison him, Kratos was in fact the true source of his torment, though Kratos insists he did the Smith God no wrong and that he is after only one Olympian. Hephaestus chuckled at Kratos' comment and told him about the Flame of Olympus. He warned him that the flames were lethal to both Man and God. Kratos then asked the Smith God where he could find the Flame of Olypmus; Hephaestus sarcastically replied that if he could find his way out of the Underworld, he could find the Flame. Kratos left the smith god as he was, sarcastically praising his lack of helpful information.
Second Encounter
After killing Hades, Kratos returned to the forge, informing the Smith God of his triumph over the God of the Underworld. Hephaestus chuckled, amused by the fact that Hades was killed. He told Kratos a bit of how he came to the Underworld. Kratos pointed towards a Hyperion Gate, and Hephaestus told him that he would need the soul of a God in order to use it and assumed it was broken, as he would have seen his wife if it wasn't. He goes on to say that he wasn't always a monster. He was once the most prized craftsman in all of Olympus. Zeus rewarded him with the marriage of Aphrodite. Hera bragged about his talents. But the day Kratos killed Ares was the day his world was torn from him, that day Zeus became the fiend Kratos sought to kill. Worst of all, he took his daughter Pandora from Hephaestus. While imprisoned in the Underworld, he kept trying to re-create Pandora, but failed again and again, so he asked the Spartan to retrieve her. Kratos showed no intention of fulfilling his request, so he reminded him of himself as a father; while Kratos was visibly touched for a moment, he left the Forge without saying anything.
Third Encounter
Kratos returned from Aphrodite's bedchambers through the Hyperion Gate, returning to Hephaestus' prison. He initially elated that Aphrodite had come to pay him a visit, but was disappointed when it was Kratos instead. He sarcastically asked him if his wife had "conquered another God of War" and Kratos told him that it should be something he should ask her himself. Kratos then asked him if he knew where the Labyrinth was - he was confused at first, but realized that Kratos intended to find Pandora and angrily told the Spartan to stay away from her, citing that he was the reason why they were both imprisoned.
As he created Pandora's Box to hold the evils of the Great War, he realized that keeping it in the Flame of Olympus would be the safest place for it. The lock was set; all that was left was a key, a way to retrieve the Box. However, because the "key" (Pandora) took a life of its own thanks to being created from the heart of the Flame of Olympus and created a father-daughter relationship with him, Hephaestus could not bear to keep the Box there and told Zeus that it would be safer on Cronos' back, as no Mortal could best the Titan. However, this was revealed to be a ruse when Kratos extracted the Box from him, and an enraged Zeus pummeled Hephaestus until he revealed the truth of his deceit. Zeus apprehended Pandora and left her in the Labyrinth, and imprisoned Hephaestus in the Underworld for his actions. He tried to convince Kratos again, but the Spartan told him that he would stop at nothing to have his vengeance.
Seemingly disappointed, Hephaestus told Kratos that the death of Zeus would outweigh losing Pandora, and told him that he would create a new weapon to give him the "vengeance that he rightfully deserves". Kratos stated that he had weapons, but the Smith God insisted on making the weapon from him. He told Kratos to find the Omphalos Stone, and that it was located in the Pits of Tartarus. Kratos entered Tartarus to find the Stone, and Hephaestus closed the doors behind him, laughing loudly, revealing his deceit - he knew the Stone was inside the Titan Cronos, and assumed that the Spartan was no match for him.
Final Encounter
Hephaestus attempting to kill Kratos.
Whilst on his quest, Kratos battled the Titan Cronos, and slew him, taking the Omphalos Stone from his body. Returning to Hephaestus, Kratos was furious, as he believed the Smith God had sent him on a suicide mission. Hephaestus pleaded innocence, claiming that he knew the Ghost of Sparta could handle himself. After completing the Nemesis Whip, Hephaestus tried electrocuting Kratos with his Ring in a final attempt to kill him, shouting, "Here is your retribution!"
Hephaestus chuckled as he watched Kratos struggle against the electricity, but panicked when he shrugged it off and attempted to pummel the Spartan with his hammer. Kratos managed to throw the hammer away, after which he used the Nemesis Whip to electrocute the Smith God, his ring falling into the lava. Kratos then hit a lever, causing an anvil spike to impale Hephaestus in the stomach. In his dying words, the Smith God pleaded with Kratos to spare his daughter, as well as begging for Pandora's forgiveness, after which he passed away.
Kratos appeared to bear no ill will towards Hephaestus for this betrayal however, as he later told Pandora that Hephaestus had died after doing what any father should do: protecting the life of his child. This is most likely because Kratos would've done the same thing were he in Hephastus's position.
