The Merlin Prophecy Book One: Battle of Kings di M. K. Hume, 2013, Simon And S

Note:
In the town of Segontium a wild storm washes a fugitive ashore. He brutally rapes the granddaughter of the ruler of the Deceangli tribe, leaving her to bear his son, Myrddion Merlinus (Merlin). Spurned as a demon seed, the child is raised by his grandmother and, as soon as he turns nine, he is apprenticed to a skilled alchemist who hones the boy’s remarkable gift of prophecy.