Okay so if I have a {Xathrid Gorgon} in play and the opponent's attackers have been declared can I use the petrifaction ability on Xathrid to stop the attack of one of the creature or will it still go through this turn?
I believe you would have to do it before attackers are declared, which shouldn't be a problem because you have a chance to respond to his declare attackers step. Although, I think that when the creature is turned into a Defender it is literally unable to attack and is pulled away from combat, I may be wrong though.
you have to do it before he declares who is attacking, once he enters attack phase, but before creatures are tapped and attacking.
edit: or before attack phase, or after attack phase, or when ever, just not when he taps a creature to attack. I believe it has something to do with no priority passing between the tapping and attack.
Once he enters the declare attackers phase you are SOL, because once he declares a creature as attacking(which he may do in the declare attackers phase) that creature is labeled as 'attacking' and this cannot be retracted. You must do so before enteringthe declar attackers phase(whether during upkeep, or main phase 1, it does not matter so long as he does not enter the declare attackers phase)
Okay thank you. Glad I checked :)