Bujin Regalia - The Jewel (LVAL-EN075) - Legacy of the Valiant Unlimited

Target 1 Rank 4 Xyz Monster you control; equip this card to that target. It gains 300 ATK for each Xyz Material attached to it. Once per turn: You can attach 1 "Bujin" monster from your hand to the equipped monster as an Xyz Material.