You can send this card from your hand or field to the GY then target 1 faceup monster your opponent controls send 1 Blackwing Synchro Monster or 1 BlackWinged Dragon from your Extra Deck to the GY and if you do until the end of this turn the targeted monster loses 700 ATK also negate its effects This is a Quick Effect if you control a DARK Synchro Monster You can only use this effect of Blackwing Chinook the Snow Blast once per turn