Death Star-vader, Chaos Universe Alththani

-Stride Step-[Choose one or more cards with the sum of their grades being 3 or greater from your hand, and discard them] this card on your from face down. :[ 1 & Choose a face down card with "Chaos" in its card name from your G zone, and turn it face up] When this unit is placed on , if you have a heart card with "Chaos" in its card name, you may pay the cost. If you do, your opponent chooses two of his or her rear-guards, and lock them. If he or she could not lock two cards, you draw two cards, choose two of your units, and they get +2000 until end of turn.