If you control a monster with 2000 or more ATK, you can Special Summon this card (from your hand) in Defense Position. You can only Special Summon "Overlay Booster" once per turn this way. If this card is in your GY, except the turn it was sent there: You can banish it, then target 1 face-up Xyz Monster you control that has material; it gains 500 ATK for each material attached to it.