"Once my name was spoken in whispers and it brought dread to this land." — The Forgotten God, when awakened in his temple.
The Forgotten God was married to the Mother Goddess. However, when she caught him cheating on her, she banished him to the Infernal Abyss and blocked all memory of him from the minds of mortals (anyone who tries to remember him quickly forgets). This is apparently "almost as bad as death" for a god, and he seems obsessed with making people remember him again.
Overlord: Raising Hell
Determined to escape the Abyss and begin a reign of terror, the Forgotten God opened several Abyss Gates across the Third Overlord's conquered lands, entrapping his subjects and condemning them to misery.
Along with the suffering of the deceased, this would eventually enable him to enter the living realm and wreak havoc on all that is of the Mother Goddess' creation. He was stopped, though, by the Third Overlord, who sought to take the Abyss for himself. In the final confrontation against him, the Overlord burnt his body to ash.
In his final breath the Forgotten God destroyed the Infernal Abyss Gate, leaving the Overlord trapped. With the Forgotten God dead, though, the Wraiths under his command pledged loyalty to the Overlord, leaving him as the new Lord of the Abyss.
Note: The Forgotten God sweep attacks appear to deal a random amount of damage. Sometimes it does nothing, sometimes 1 bar of Health, and other times reducing the Overlord from full to 2/10 of hp (with fully upgraded Arcanium Armor). Arcanium Armor with at least 20-25% Health Regeneration is recommended if you are not familiar with his fight.
Taking the fight to The Forgotten God themselves, the Overlord and his minions arrive in his own temple. The Forgotten God is summoned by the Overlord's jester, and keeps to the middle of the room. If not approached, he will swipe wide with his hands, obliterating minions. However, it would seem his attacks do a random amount of damage, ranging from barely anything to nearly killing the Overlord.
The main goal of the fight is to bring his own temple crashing down around him. Approaching the edge of his pit, he will utter a line before violently smashing his face into the ground, taking several moments to remove his head while the Overlord's minions attack. They can only do minimal damage before The Forgotten God begins to ignore any more. He will then seem to charge up, before now violently ramming his face against the outer walls trying to hit the Overlord and/or his minions. The trick is to have him smash one of 4 pillars holding up the ceiling, causing it to crash down on him.
2 pillars are reachable by the Overlord, marked by an abyssal stone wall. The final 2 pillars are in the far back, with rubble preventing the Overlord himself reaching them, but not his minions. After half of the pillars have been destroyed, the Forgotten God will use some form of tornado spell, which can sweep up to 10 minions and destroy them. To avoid this attack, there are crevices in the wall that can protect the minions if they are in them. Wraiths are summoned in infrequently, but should not be a major concern.
After all 4 pillars are destroyed, the Forgotten God will attempt to roar, only to be pinned down the ceiling, leaving him at the mercy of the Overlord. Striking the final blow on the Forgotten God and incinerating his body, he utters his final grievances as he dissipates. The Abysses are under the control of the Third Overlord, but at what cost?
Personality and Traits
The Forgotten God has a serpent-like form with many tusks and bones, though wears a golden mask which completely covers his seemingly skeletal face.
He is incredibly vain and condescending, seeing all mortals as beneath him, including the Overlord, and regards the Mother Goddess with utmost contempt for punishing him, despite having brought her wrath upon himself. Since he hates the Mother Goddess with every fiber in his body, he also greatly despises the mortals that worship her the most, the Elves, and never wastes an opportunity to inflict on them all kinds of pain and humiliation with truly sadistic passion. But the heroes are the main targets of his hatred; the Seven Heroes had everything - fame, wealth, adulation - and they wasted it... almost like him with the Mother Goddess. Probably his strong disdain for the heroes is his way to express his self-hatred for cheating on his wife, as he sees much of himself in them.
He is strongly obsessed with his undying desire to be remembered again by the mortals, in order to put an end to the terrible torment that the Mother Goddess imposed on him. By opening the Abysses he tried to claw his way back into the world, making every creature suffer as he did.