The Sorcerer's Apprentice by Christopher Bulis

The Land of Elbyon is a place populated by creatures of fantasy, where myth and legend rule. Elves and dwarves live in harmony with mankind, wizards wield arcane powers and armoured knights battle monstrous dragons.

But the Doctor doesn't believe in magic, and it seems that Elbyon has secrets to hide. The TARDIS crew find a relic from the thirtieth century hidden in the woods. Whose sinister manipulations are threatening the stability of a once peaceful lane? And what part does the planet play in a conflict that may save an Empire, yet doom a galaxy? To solve these puzzles, and save his companions, the Doctor must learn to use the sorcery whose very existence he doubts.