You know what they say, curiosity killed the Early Man who then became possessed eternally by fire spirits.
The Early Risers were among the first Waking Men to trek the surface of the Auldensphere, each saw the sights and wonders of a land previously unknown to any race with the intellectual capacity to appreciate it. They kept no documents or records. Those that came after would still tell their stories of discoveries, and on the darkest nights when the sky was obscured by clouds and they believed themselves hidden from the eyes of gods, they told the grimmer tales of how many of the Early Men befell strange and star-crossed fates, coming into spiritual prevalence at the cost of their humanity through suffering that immortalized them on the Auld.
Once such casualty of the early unnamed explorers is now known as Wakatosh, the god spirit penance and atonement.
The Myth of Fire[]
On a night the pack of Early Men camped near the Thrashing Cliff in the Belly of the Auld (now known as the Kauld) they sent of member of the group out to gather wood to build forest beds for the night. While he looked for sticks in the coming cerise of the full moon, he noticed a glow in the ground, burning deep crimson. The ever-curious adventurer took on of the larger branches, wedged it in the hole, and upon pushing it down found the crack continued to split further in the direction he pushed. The Early Man repeated this action again and again, until the night was waning and his restless brothers came to find him.
By the time the other mortals reached him, he had cracked a ring in the Belly of Auld that spread the horizon and back. Just as his brothers breached the ridge to see to blood-red lining in the land, the surface of the circle shattered and spirits of flame danced up to the surface, dying as they rose and charring in the cold night. The dying spirits of fire concealed in the crusts of the Earth demanded a sacrifice for letting the cold of the air on breathe into their subterranean chambers. It took little deliberation before the decision was reached to send the offender with the branch to the fiery bellows below ground, and the charred corpses smothered him in steam and suit, burning him as he howled, soon finding new his body as their new vessel. For this, the Early Man was bound and dragged below to serve as penance for bringing the surface world to the world below.
It is said that when the fire spirits returned to the depths and sealed the cracks in the land, small glowing lights of embers and flame were left on the world above, and this was how fire came to be on the surface of the Auld.
Early soothsayers and spirit walkers claimed to have connected to the world below when mortals began to wield their power of homage, and reported that an Early Man now known as Wakatosh was still in possessed possession of the spirits of fire, now forced further down after the world's surface cooled, and they kept that man in constant coals as atonement for letting their sacred flame make its way to the land above.
Their anger over mortals learning their secret of fire exploded through the surface in the form of the largest volcano in Kauld, the Ring o' Fire.
Wakatosh has few followers, save the occasional pyromaniac looking for extra heat, but as the original man of penance those who must subject themselves to punishment in order to atone pay him homage, even if not meaning it, and keep his burned body fueled by fire spirits among the lesser deities, continuing the suffering in exchange for fire. Every fire set sends trace amounts of Aether, which keeps Wakatosh on fire, which his flaming albatross to bear.