Vulpikeet (IKO) from Ikoria: Lair of Behemoths, available at 401 Games Canada.

• Rarity: Common
• Finish: Normal
• Artist: Leesha Hannigan
• Card Text:
  Mutate 2W (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
  Flying
  Whenever this creature mutates, put a +1/+1 counter on it.