2 Books Found

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"A series of short books (for kids) about a young boy learning to be a mage. He starts out with next to no skill - I distinctly remember a scene where he's trying to light a candle and all he can manage is to make the middle collapse. He later grows in skill and has great magical reserves. In some of the later books there's time travel, and he also spends time voyaging with a knight (there's a scene where the knight has to cut a tree down with his sword). An evil knight called Thibault makes an appearance in one of the later books. He also learns illusion magic with a travelling circus at one point"