Captain Zapp Brannigan

At the beginning of combat on your turn, target nonland permanent you control becomes a Vehicle artifact until end of turn. Its base power and toughness are each equal to its converted mana cost/mana value. It has crew 2 and "Crash Land — Whenever this Vehicle deals damage, roll a six-sided die. If the result is equal to this Vehicle's converted mana cost/mana value, it deals that much damage to any target (creature, player or planeswalker), then sacrifice this Vehicle."