Overcharged Amalgam (VOW) from Innistrad: Crimson Vow, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Mike Jordana
• Card Text:
  Flash
  Flying
  Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
  When Overcharged Amalgam exploits a creature, counter target spell, activated ability, or triggered ability.