Flash {1}{U}
Instant
You may put a creature card from your hand onto the battlefield.
If you do, sacrifice it unless you pay its mana cost reduced by up to {2}.
Fling {1}{R}
Instant
As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature’s power to any target.
我可以用Flash放一只生物进场，
不付(或付不出)他的mana-2的费用，但是用fling牺牲他以造成伤害吗?

没办法，付o2或牺牲是闪现还在结算中执行的

了解，所以Phyrexian Dreadnought这种进场触发的才能牺牲囉

flash那两行字是同一个异能当flash开始结算的时候，就要从第一个字走到最后一个字

现在风行的写法会是When you do, 牺牲 如果这种就可以但Flash已经够臭了 应该不可能改成这个更强的版本