Treeborn Frog (CP04-EN020) - Champion Pack 4 Unlimited

If this card is in your Graveyard during your Standby Phase and there are no Spell or Trap Cards on your side of the field, you can Special Summon this card to your side of the field. This effect cannot be activated if there is a face-up "Treeborn Frog" on your side of the field.