Crimson Shard. The Crimson Series, #2

The last Atlantean has been vanquished, but his sorcerous curse remains, threatening to blanket mankind in a veil of devastation. Sorsha-the famed mercenary leader of men who struck the killing blow through the heart of the last Atlantean-was cursed by his amulet to complete his quest; carve out his kingdom, and use all the sorcery of Atlantis to obtain it. Corrupted by the amulet, Sorsha assumes the name of her alter ego, the Raven, and takes on the ferocious traits of the last Atlantean.
Using her new found power, as the world's first sorceress, Raven sets out to complete her quest to carve out her kingdom with the aid of women she bestows her abilities upon, and men she transforms into obedient abominations the likes of which dwarf even the last Atlantean's unnatural creations. By Raven's side, and unaltered due to their history, Lexa uses her skills as a master thief to gain favor and attempt to free Sorsa from the Raven's grasp.
Unbeknownst to Lexa, Thor, their former companion and sword for hire whose yet to be bested in battle, has made a similar vow. Thor, attempting to track down Raven and Lexa, discovers his cousin Eric has inadvertently created an army of his own-one comprised entirely of bloodthirsty wolves that walk like men. Now, Thor and Lexa must each use their wits and skills to save Sorsha from her alter ego, defeat the sorceress plague that Raven, the last Atlantean, and Eric have set loose.
All the while decoding the cryptic Atlantean foretelling of the devastation to befall the world before it's too late.