Celestial Archon (C15) from Commander 2015, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Matt Stewart
• Card Text:
  Bestow 5WW (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
  Flying, first strike
  Enchanted creature gets +4/+4 and has flying and first strike.