This Harry Potter Heat Changing Mug features the Marauder's Map design with the infamous phrase "I Solemnly Swear" on it. The mug transforms when hot liquid is poured into it, revealing hidden details from the map. Perfect for Harry Potter fans, this collectable item is a must-have for those who appreciate the magical world of Hogwarts. Whether you're enjoying a hot beverage or displaying it as part of your Harry Potter collection, this mug adds a touch of enchantment to your everyday routine.
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