The Ten are the fragmented pieces of an ancient soul, condemned by gods now long forgotten to never know rest. Perpetually reincarnating, condemned to remember the weight of the past, the soul eventually shattered beneath the weight of the past, one becoming ten, each still unable to find an end.
Over time, each soul-shard has continued to grow and evolve, becoming unique entities in their own right, all filled with a hatred of the gods for condemning them to this endless, bitter cycle of eternity. It is this hatred which drives them to work plots and schemes on a span of time that dwarfs any mortal race, for the goal of the ultimate kind of genocide: the ending of the gods themselves, in revenge for what was done to them.
Long ago, in times so ancient not even the muses who safeguard history know of it, a mortal soul ran afoul of the gods of that lost era; what the crime was is lost, as is the identity of the gods who were involved. Even the Ten barely remember that distant time when they were one; the only clear memory is the curse the gods laid upon the mortal, to never know rest and ease with the passing of life.
The curse resulted in the soul’s reincarnation; and after a few years of life, the return of memory. It seemed like a twisted kind of boon, a strange form of immortality. Plans could be made on the order of multiple lifetimes, belongings cached to ensure prosperity in future lifetimes. Knowledge could be gained in amounts and depths that defied those who would eventually pass on to rest in the eternal afterlife.
Mortals minds are not meant to handle the passage of time on such scales, however; as knowledge accumulated, so did the strain of living, seeing lifetime after lifetime of mortal friends and family pass away, an endless chain of graveyards to bear witness to time’s passage. Soon enough, even the changing of the natural world became apparent.
Madness struck, and lasted several lifetimes - an incurable dementia, despite the best efforts of those who knew nothing of the divine curse. And so the gods who had wrought it looked upon their work, and felt it good; then they moved on, leaving the cursed one to struggle onward through lifetimes of madness and perpetually growing memory.
Then came one lifetime when, as memory returned, not only the psyche but the very soul broke beneath the flood, fragmenting into squabbling, ruined pieces. It was a madness never seen before, and in short order the poor, fragmented one was slain out of simple mercy.
Once broken, most souls simply dissipate, unable to exist but too ruined to find any peace other than oblivion; yet the curse of the divine was too powerful to allow even this bitter rest to the broken one. Each soul-shard, a mere caricature of an integral thing, was reborn distinct - and lucid, the new shape of things restoring to the collective whole a strange kind of sanity. As the most coherent of the Ten noted, it was a calm on the far edge of the stormy seas of madness.
They were, for the first few lifetimes this way, simple caricatures, personality fragments given distinct lives of their own. Often things went poorly; most of the ten fragmented pieces were ill-suited for living true lives. Over time, however, each grew more complex, more capable of life as a distinct creature; over a handful of lives, they developed from mere caricatures into creatures who were driven by their original aspect, but no longer simply echoes of it; and always, tied by spiritual threads, they were drawn together.
Then came something unexpected, so unlikely as to be unbelievable: one of the gods who had delivered the curse died as the last of his mortal followers passed away, taking the knowledge of his ways to the grave with him. It was a thing never seen before, and to the Ten who had been One, it was a revelation that even the Divine could be ended. It brought hope that perhaps they could bring an end to their endless chain with the ending of those who had inflicted it.
Thus it was that the Ten’s alliance across the ages began, a ceaseless struggle against Divinity and Faith. Each waged the war as they saw fit, working together and struggling against each other by turn, undermining the faiths of the gods who had cursed them. Over the lifetimes, as their collective skills improved and they began to plot and scheme on a more-than-mortal timespan, the gods began to weaken, and then fall to their efforts; that new gods arose was of no concern, as they sought merely to end the ones who had cursed them, hoping to be free of their divine shackles.
Perhaps, had the Ten still been One, they might have succeeded. Perhaps not; it is a moot point, as when the last of the gods who had afflicted them had fallen, the Ten quietly waited the rest of their lives, hoping to find rest at last. It was not to be; perhaps the sundering of the soul was to blame, or perhaps the curse lingered by the mere presence of divinity in the world. Regardless, the Ten, as they died, were reborn once again. For a few lifetimes, they despaired - then together concluded that if the passing curse of the gods could bring such suffering, then surely the world would be better off without such beings. They had proven that mortals could strive against the gods and triumph - surely that was proof enough that mortals had no need of gods in the first place.
Thus did they begin their true war - a war to exterminate all the gods. Divine genocide was their goal, and remains their goal in the modern era. Each has become a near virtuoso of a handful of disciplines, and even though their direct goals often conflict as each operates according to their own methods, their final goal is what drives each one onward in plots that span the lifetime of entire civilizations.
A world without gods, where the mortals of the world are not compelled to bow and scrape in temples, not coerced to sacrifice the fruits of their labors, and not subject to divine temper tantrums. This is their goal, and the fate on which they hang their final hope of peace - for surely if all the magic of the divine leaves the world, the curse which binds them to this endless chain of lives must pass on as well.
Ten shards, each one grew from a prominent aspect-of-self in original soul.
Greed, Pride, Anger, Compassion, Freedom, Curiosity, Logic, Control, Sorrow, Mirth all possible shard-bases. Maybe others.
Inner circle of the Ten. Manipulators on epic timescale. Want to kill the gods off, but end up amassing wealth, power as side effect of long-term goals.
One soul, condemned by forgotten gods and broken by the weight of ages; now, fragmented to ten pieces, it carries on a quest of deicide across eternity…