Impulsive Maneuvers (ODY) from Odyssey, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Dave Dorman
• Card Text:
  Whenever a creature attacks, flip a coin. If you win the flip, the next time that creature would deal combat damage this turn, it deals double that damage instead. If you lose the flip, the next time that creature would deal combat damage this turn, prevent that damage.