The Magic Thief by Sarah Prineas

After street thief Connwaer steals a wizard’s stone from the formidable Nevery and, against all odds, survives touching it, he’s taken in as an apprentice in the city of Wellmet, where the flow of magic is mysteriously fading. While hunting for his own locus magicalicus and learning the rules of spellcraft, Conn navigates guild politics and back-alley dangers to uncover who is siphoning the city’s power. His quick wits and stubborn loyalty drive a daring plan to stop the saboteur and restore hope to a city on the brink.

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