Hero Deity of the Polar Extremity, Marduk (V-SS05/S07EN) [Premium Collection 2020]

"[Stride]-Stride Step-[COST][Choose one or more cards with the sum of their grades being 3 or greater from your hand, and discard them] [Stride] this card on your (VC) from face down. [AUTO]{G zone}:When your vanguard attacks, if your vanguard is grade 3, [COST][Counter-Blast 1 & Soul-Blast 6], stride this card on your (VC) as [Rest] from face down, and it gets the [Power] and [Critical] one of your heart cards had got from trigger effects this turn until end of turn. Change the attacking unit for this battle to this unit."