If you’re out to cause mischief then a magic map of the building with the live location of everyone inside will come in handy! This is exactly how the Marauder’s Map provided Harry Potter with all of the information he needed to sneak around Hogwarts.
The outside of the mug reads “I solemnly swear that I am up to no good”, the exact incantation required to activate the map. Add a hot drink (in a mischievous way if you like) and the black shroud around the mug dissolves away to reveal a trail of footprints as well as the concealing spell to hide it again. It’s a neat little piece of Harry Potter that any fan of the books or films will love!
Heat changing mug with the Marauder’s Map
Official Harry Potter merchandise
When cold reads “I solemnly swear that I am up to no good”
Foot prints and concealing incantation appear when hot drink added