Background Dragon (MP19-EN008) - 2019 Gold Sarcophagus Tin Mega Pack Unlimited

If this card is in the GY and you control no cards: You can Special Summon both this card, and 1 Level 4 or lower Dragon monster from your hand, in Defense Position, but banish this card when it leaves the field. You can only use this effect of "Background Dragon" once per turn.