The imp soul in a box is a Treasure Hunter reward first introduced with the Raising Rituals promotion. The imp can be negotiated with to select an alteration glyph which will be applied during the next ritual started with the item in the player's backpack. Upon beginning the ritual with a glyph selected, one imp soul in a box is consumed and removed from the player's backpack, and its chosen glyph cannot be modified until the ritual is completed.