Dark Dragon, Phantom Blaster "Diablo"

(Released when both players' vanguards are grade 3 or greater!)-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 named "Dark Dragon, Phantom Blaster "Diablo"" from your G zone, and turn it face up] If the number of face up cards in your G zone is two or more, until end of turn, this unit gets +10000/ +1, and ":[Choose three of your rear-guards, and retire them] When this unit attacks a vanguard, you may pay the cost. If you do, your opponent may choose two of his or her rear-guards, and retire them. If two rear-guards were not retired, your opponent cannot call cards from hand to until end of that battle.".