Arbor Colossus (THS) from Theros, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Jaime Jones
• Card Text:
  Reach
  3GGG: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous)
  When Arbor Colossus becomes monstrous, destroy target creature with flying an opponent controls.