The Lightsworn Society - The Beasts of Shadow and Light, #1

The five houses of the earth have been ruled by Ramiel the Mage for over 1000 years, and over that millennium all have prospered and lost. The house of mankind has suffered the most, and gained little in return, but now the greyhearts have risen from among them. The Lens of Ramiel can transcend both time and space (seeing all within its range), but it cannot pierce the hearts or minds of the greyhearts.
Although all others who've used the Lens have gone blind, this unique breed of human may be able to use it and put a stop to the injustice of the immortal circle of Magi. He searches for them. He turns all against them.... But he will find that the brave and fearless race of mankind will not be defeated so easily.