Counterbalance + Stifle

[Mantis]

The following situation occurs: My opponent has Sensei's Divinning Top + Counterbalance and I want to get through a Pernicious Deed.
If I play the Deed and my opponent responds by activating SDT and putting a spell with cmc 3 on top, then activates Counterbalance; can I Stifle the Counterbalance activation so my Deed will resolve?
And what happens if my opponent taps the SDT in response and puts it on top to use the Counterbalance effect to counter the Stifle? Will the card with cmc 3 still be flipped and thus counter my Deed?

Thanks, Mantis.

[Shock Wave]

Stack:

Top Activation
CB Trigger
Deed

Here's what happens, assuming you've allowed your opponent to resolve the Top activation and put a 3cc spell on top of his library:

Your opponent has priority. If he passes priority to you and you pass back, then the CB Trigger resolves. Otherwise, if you choose to play a Stifle targeting the CB Trigger, here's what the stack will look like at that point:

CB Trigger
Stifle
CB Trigger
Deed

As you can see, casting the Stifle has caused the CB to trigger again on top of it. If your opponent has mana free, and has a 1cc card on top of his library in addition to a 3cc card, he'll be able to counter both the Stifle and the Deed. This can be achieved because he'll have priority to make a play before both CB triggers resolve.

Now, let's assume your opponent decides to tap SDT in response to the CB Trigger for the Stifle. Here's how the stack looks like, and how it will resolve (assuming no other additions to the stack):

SDT activation
CB Trigger
Stifle
CB Trigger
Deed

The Top resolves and ends up on top of your opponent's library. The CB trigger resolves and flips the Top, countering the Stifle. The next CB trigger resolves, and flips the Top, which does not counter the Deed.

Hope that helps.

[Harlequin]

Note that you only reveal the card when the ability resolves.  So you wouldn't see the 3cc card, and therefor wouldn't "know" for sure if the top card was a 3cc card or not.  Once the card is revealed you have lost your chance to respond with stifle. 

That's really imporant to keep in mind.  So really you have to decide to stifle without really knowing for certain if your opponent has the 3cc card.  They could go "whoo GOT THERE!" or "CRAP!" but when I used to play top sometimes I would try to fake people out to bait stifles.

[Clariax]

If I play the Deed and my opponent responds by activating SDT and putting a spell with cmc 3 on top, then activates Counterbalance; can I Stifle the Counterbalance activation so my Deed will resolve?

First off, Counterbalance is never activated.  The ability is triggered.  And the ability triggers when you play the spell, the opponent doesn't choose to have it trigger, it triggers automatically.  Revealing the top card happens as part of the resolution of the trigger, so you cannot wait to see if he's going to reveal a card, or what card he's going to reveal, before deciding whether you wish to counter the trigger or not.

And what happens if my opponent taps the SDT in response and puts it on top to use the Counterbalance effect to counter the Stifle? Will the card with cmc 3 still be flipped and thus counter my Deed?

Thanks, Mantis.

If the Top is put on top of library before the 'Counter Deed' trigger resolves, then unless he has some other library manipulation effects available, it would be the Top he reveals (if he chooses to reveal at all) which would not counter the Deed since the CMC is different.

[Mantis]

Thanks guys, that clears things up! I just got a bit confused by the complexity of the play and lost track.