What is the rule for the double damage from rolling a crit in combat in PFS 2nd edition games? I thought the rulebook has you double the amount rolled on the die, but my GM says that the Guide to PFS play states that you roll an extra die and add them together instead. I just read through the 2nd edition guide and see no references to it. I'll go by what the GM asks for, but I'm just curious what the official rule is for when I start GMing some 2nd ed games. Thanks.