You can target 1 "Superheavy Samurai" monster you control; equip this card from your hand or field to that monster you control. The equipped monster is treated as a Tuner. If you have no Spells/Traps in your GY and this card was equipped to a monster by this card's effect: You can Special Summon this equipped card. You can only use this effect of "Superheavy Samurai Soulgaia Booster" once per turn.