Stardust Assault Warrior

1 Tuner + 1+ non-Tuner monsters When this card is Synchro Summoned while you control no other monsters: You can target 1 "Junk" monster in your GY; Special Summon it. You can only use this effect of "Stardust Assault Warrior" once per turn. If this card attacks a Defense Position monster, inflict piercing battle damage.