Plasmacro Cannon Mk. I

In addition to this card's mana cost, you must sacrifice an Invented Invention Inventor. Cast this spell with 2 durability counters. You may block attacks with this artifact. Remove a durability counter each time you do this. If this card loses all it's durability counters, destroy it and do 2d3 damage to every creature and planeswalker on the battlefield.
•{t}{w}{u}{b}{r}{g}, deal 15 damage to any target. If a player would lose due to this damage, instead reduce that player's life points to 1.