In more recent times the process continued without intervention, with the tanar'ri emerging from sins on their own. Several varieties of the chaotic fiends had to be coaxed and shaped into existence by the obyriths, particularly through the aid of the sibriexes. However, the original tanar'ri breeds were not truly born from the first humanoid souls to enter the Abyss, but rather forged from them.

Unlike their obyrith progenitors, who were spawned directly from the heaving flesh of the Abyss, the tanar'ri emerged from the more fertile soul of mortal spirit. For example, both the baatezu and tanar'ri could emerge spontaneously from their native planes, but the tanar'ri blossomed from the chaotic maelstroms of the Abyss far more frequently than the baatezu could pull themselves out from Baator's unfeeling order and rigid ground, as was to be expected from somewhere as structured and regulated as the Nine Hells.

The tanar'ri were an incredibly prolific race, outnumbering their baatezu rivals to a staggering degree and possessing a wide variety of advantages when it came to the numbers game. They care for nothing but themselves, and they don’t even care about themselves all that much. They see the living as toys to be savagely abused and then discarded. “Purveyors of ill intent and creatures of utter cruelty, it's likely that the tanar'ri are the most mean-spirited and thoroughly evil monsters in existence. Whether they arose naturally from sins and spirits, or were shaped by evil gods or other powerful demons, all tanar'ri were embodiments of vice, depraved inner demons spawned from the darkest corners of mortal minds. Tanar'ri were the dominant race of demons in the Abyss, evil souls warped by its raw chaos into manifestations of mortal failing.

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