A harrowing return to their world has left the Tier floundering. Chased from Vilhena by the nebulous shadow of the creature that destroyed their people, Ales and Liassa must find safety for the young Tier now in their charge. Without anyone to turn to, Ales and Liassa are forced to flee to the only place Liassa can imagine they will find some measure of refuge. Into the vast sea of trees known as the Black Wilds, the Tier will find that no place is truly free of the infection that has spread across their world. In this place, they will find a piece of their past in the hands of those who are unaware of its danger. To set things right, the Tier and their young charges will spread themselves to the corners of the Black Wilds, where they may discover answers to a single burning question: Who among the Ryhim has discovered the power of the Probability Matrix? Seeking the answer will reveal to them an infestation that could raze all of the Black Wilds and destroy the very people that the Tier were meant to protect, but curing it could lead them to a reward greater than they could hope for.