Whispering Madness (GTC) from Gatecrash, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Clint Cearley
• Card Text:
  Each player discards his or her hand, then draws cards equal to the greatest number of cards a player discarded this way.
  Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the exiled card without paying its mana cost.)