Whispersilk Cloak (DST) from Darksteel, available at 401 Games Canada.

• Rarity: Common
• Finish: Normal
• Artist: Luca Zontini
• Card Text:
  Equipped creature is unblockable and can’t be the target of spells or abilities.
  Equip 2 (2: Attach to target creature you control. Equip only as a sorcery. This card comes into play unattached and stays in play if the creature leaves play.)