The Phantom Knights' Rank-Up-Magic Launch

During the Main Phase: Target 1 DARK Xyz Monster you control with no material; Special Summon from your Extra Deck, 1 DARK Xyz Monster that is 1 Rank higher than that monster you control, by using it as the Xyz Material, and if you do, attach this card to it as additional material. (This is treated as an Xyz Summon. Transfer its materials to the Summoned monster.) During your Main Phase: You can banish this card from your GY, then target 1 DARK Xyz Monster you control; attach 1 "The Phantom Knights" monster from your hand to that monster as material.