Like let's say thoughtseize or thought-knot seer targets an instant card, can you use that instant card right away in response to them declaring that it will be discarded?
No, because when it is selected the effect is already resolving, and you cannot interrupt a resolving ability or spell, except with mana abilities or morph (since they don't use the stack).
No, because when it is selected the effect is already resolving, and you cannot interrupt a resolving ability or spell, except with mana abilities or morph (since they don't use the stack).
Almost, Morph is a special action but you still need priority to turn face up. So you can't interrupt abilities with it.
No, because when it is selected the effect is already resolving, and you cannot interrupt a resolving ability or spell, except with mana abilities or morph (since they don't use the stack).
Almost, Morph is a special action but you still need priority to turn face up. So you can't interrupt abilities with it.
Like let's say thoughtseize or thought-knot seer targets an instant card, can you use that instant card right away in response to them declaring that it will be discarded?
When dealing with spells and abilities the general rule is that once they start resolving, no one can do anything until they finish. So once Thoughtseize looks at your hand, it has begun resolving and no one can do anything until it finishes.
You should also known that Thoughtseize doesn't target cards it targets players. You can't target cards because you don't know them until you see their hand.
So no, you can't use a card once an opponent chooses it. You can, however, cast it before your opponent sees your hand. But not after.
No, because when it is selected the effect is already resolving, and you cannot interrupt a resolving ability or spell, except with mana abilities or morph (since they don't use the stack).
Almost, Morph is a special action but you still need priority to turn face up. So you can't interrupt abilities with it.
You generally need priority to activate mana abilities too (although you also get an opportunity to activate them if an effect asks for a mana payment). Mostly it doesn't matter, but there are some mana abilities that have side effects, such as Chromatic Sphere, Millikin, etc.
Almost, Morph is a special action but you still need priority to turn face up. So you can't interrupt abilities with it.
Oh cool. That makes more sense.
When dealing with spells and abilities the general rule is that once they start resolving, no one can do anything until they finish. So once Thoughtseize looks at your hand, it has begun resolving and no one can do anything until it finishes.
You should also known that Thoughtseize doesn't target cards it targets players. You can't target cards because you don't know them until you see their hand.
So no, you can't use a card once an opponent chooses it. You can, however, cast it before your opponent sees your hand. But not after.
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