Hi, I just had a quick question regarding Mxy.

Say I play a figure with prob control. I roll an attack, I choose to let the roll ride, Mxy replaces one of the dice with his d6, can I as the controller then declare I want to prob control that role? Or do I have to ask the player of Mxy if he wants to replace it before I declare prob control? Because mxy's trait says nothing about I can't reroll his d6 once he's replaced one of mine.

It's situational, but I'd like some clarification.

As far as I can tell, it triggers the same time as prob. So you can prob the roll before or after it gets modified.