Swarmborn Giant (JOU) from Journey into Nyx, available at 401 Games Canada.

• Rarity: Uncommon
• Finish: Normal
• Artist: Jaime Jones
• Card Text:
  When you're dealt combat damage, sacrifice Swarmborn Giant.
  4GG: Monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)
  As long as Swarmborn Giant is monstrous, it has reach.