Engineered Explosives

Often made from brass or gold, this cylindrical object is made from several layers of material, all of which can be spun and twisted until they reveal a small handle at one end, and a single clear gem at the other. While holding the cylinder, a spellcaster can cast any spell of 3rd-level or higher from one of any of the 8 schools of magic, storing the spell into the gem as they do so. Doing so causes the gem to temporarily turn one of several colors, before returning to its original clarity. The gem can store up to one spell from each school of magic. At any time, as long as the gem is holding at least one spell, you can pull the handle on the cylinder’s other end, setting the explosive’s timer. After 5 rounds, the cylinder creates a magical explosion in a 60-foot radius, plus an additional 5 feet for every spell stored in the gem. All creatures, objects, and magical effects within the radius of the blast are affected by the dispel magic spell as if it were cast using a spell slot whose level is equal to 3 + the number of spells stored in the gem.