Sunset Edge, Duskblade RRR

[AUTO](RC) Generation Break 1 (This ability is active if you have one or more face up G units in total on your (VC) or G zone):[Counter Blast (1)] When this unit attacks a vanguard, if this unit is boosted, you may pay the cost. If you do, choose one of your opponent's grade 2 or less rear-guards, and lock it. (The locked card is turned face down, and cannot do anything. It turns face up at the end of the owner's turn.)