No one knows who or what created the Abyssal Heart, or why it existed. The object, a massive black and red pulsing stone, promised mastery of all reality to Tharizdun, if only he claimed it. Tharizdun, unable to resist the promise of limitless power, claimed the Heart. At that moment, anything good within Tharizdun perished for eternity, replaced by the undying evil of the Abyssal Heart, and became known as the Mad God.
Ultimately, the corruption already contained within Tharizdun’s being combined with the power of the Abyssal Heart. Over time, Tharizdun became a malignant, dangerous, and destructive entity – an entity that posed a threat to all of creation. His hubris led him to challenge the Overgod and the Gods of Dawn. Although he came within moments of victory, the betrayal of his lieutenants led to Tharizdun’s defeat.
Torog forged an impenetrable prison in which to contain both Tharizdun and the Abyssal Heart. Torog also fashioned mighty chains for holding Tharizdun. Thus did the Mad God become known as the Chained God.
Buried with the Chained God, the Abyssal Heart unleashed its fury. Although it could not awaken Tharizdun or free him from captivity, its sinister power completed the final changes to the Abyss. To this day, the Abyss remains one of the most horrific, foul, tainted, and lethal places in all of creation. Buried at the bottom of the Abyss stands a prison of black iron. Within these walls, the Chained God slumbers in fitful sleep, dreaming of his return and final revenge.
Numerous prophecies and legends speak of the release of the Chained God, often as if this event is inevitable. Regardless of the enmity between gods and primordials, no sane being or creature would ever want to see Tharizdun released. From the noblest deities of good down to the most benighted and perverse servants of evil, no one looks forward to the Chained God’s release. Unfortunately, dozens of insane chaos cults devote their lives and souls to freeing the dark god from his prison. These cults may well hold the key to Tharizdun’s prison, in spite of their twisted insanity.
Meanwhile, still lying in the depths of the Abyss, the Abyssal Heart continues to grow, pulse, and hunger. Its inimical power corrupts all creatures, taints all that is good, warps everything it touches, and eventually dominates even the strongest of wills. If anything in creation represents pure evil, it is the Abyssal Heart.