Merlin's Legacy, Book 4: Shadows of Camelot

Warrior and sorcerer Truan is sent back in time to the side of Merlin the magician, where, armed with the sword Excalibur, the Holy Grail, and the Prophecy of Cassandra, he struggles to save the life of the woman he loves. Original.

Beautiful Amber is the only survivor of a brutal Viking attack, and even though her wounds heal, she refuses to speak. Powerful, handsome Truan Monroe loves Amber, but he knows that he can never claim her; beneath his pretense of being a poet and maker of simple magic tricks lurks a truth he can never reveal: Truan is a mighty warrior and sorcerer with incredible powers, including the ability to change shape. When Amber is kidnapped and taken through time to Camelot by evil Gareth, Truan discards his disguise and is recognized as the son of Merlin, the powerful magician of Camelot. Truan must save Amber, so he follows her through the centuries to Camelot, where he wages war against Malagraine, Lord of Darkness, to win Amber's freedom.