Floating Shield (TOR) from Torment, available at 401 Games Canada.

• Rarity: Common
• Finish: Normal
• Artist: Keith Garletts
• Card Text:
  As Floating Shield coms into play, choose a color.
  Enchanted creature has protection from the chosen color. This effect doesn't remove Floating Shield.
  Sacrifice Floating Shield: Target creature gains protection from the chosen color until end of turn.