The Adventures of Merlin Series by Ben Vanstone, Jacqueline Rayner, Simon A. Forward, Julian Jones

When fire erupts in her chamber, Morgana fears that she started the blaze herself - using magic.Frightened by this new power, Morgana seeks out the Druids who Merlin believes can help her. But Uther, believing she has been abducted, sends and army after her.Can Merlin find Morgana before innocent lives are lost?

Merlin arrives in bustling Camelot eager to make his way in the world and with a sense that some greater destiny is calling him. But he soon finds that amidst the excitement there is a darker side to Camelot. Magic is outlawed here, so Merlin must keep his unique magical talents a closely guarded secret...From the BBC TV series: Merlin

When Arthur kills a unicorn, Merlin knows that terrible consequences lie in store for Camelot and its people. After a hunting trip in the forest, Arthur is fatally attacked by a savage beast. As the Crown Prince lies dying, Gauis knows that dark magic is at work and Merlin is the only one who can save him.