This small, metallic and pocket-able talisman appears to be nothing more than a crushed piece of metal. Upon holding this piece of goblin ingenuity, you feel an unmistakable surge of electricity coursing through your veins; your eyes might widen in excitement or your body may begin to vibrate with energy. You inherently know how to unleash it's power and begin your domination of the world, one step at a time.
Whenever you deal damage using a weapon, spell, or spell-like ability in combat, you may invoke the power of The Spark of Madness as a free action. Using The Spark of Madness in this way, you may add an additional 1d6 of lightning damage to your initial damage. However, before you roll the additional 1d6, you must declare two of the six numbers on the die.
If you do not roll any of the declared numbers, you may add the number on the dice as additional lightning damage.
If you roll one of the declared numbers, you do not deal any additional lightning damage and instead gain one Madness Stack
Upon reaching three Madness Stacks, your initial attack is cancelled, and you gain the status condition of stunned until the beginning of your next turn as you lose control and begin to maniacally laugh. For example, if Brin the Fighter had two Madness Stacks, landed an attack, elected to use the Spark of Madness but rolled one of her declared die 6 numbers, her attack no longer lands as she interrupts herself with maniacal laughter.
Madness Stacks reset on the completion of a long rest.