As long as you get to the point of attacking, and the trigger is on the stack, removing Brimaz will not stop the ability from resolving. If the opponent wants to ensure no token is created, then they need to destroy it before Brimaz is declared as an attacker. The latest they can do this is in the Beginning of Combat Step. Note, that you must give them a chance to do this and cannot just rush past this step in order to attack before they can respond before attackers are declared.
Please ask rules questions in the Magic Rulings section in the future.
Like WizardMN said though, you have to give your opponent a chance to respond to changing phases. If you announce that you are moving to "declaring attackers" and they don't want to do anything at that point, then depending on if you are attacking a player and they are defending themselves will not stop the trigger but if someone is trying to stop you from getting a token, you can't skip their priority to remove your commander before you can attack.
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I have officially moved to MTGNexus. I just wanted to let people know as my response time to salvation decks being bumped is very hit or miss.
Brimaz, King of Oreskos
As long as you get to the point of attacking, and the trigger is on the stack, removing Brimaz will not stop the ability from resolving. If the opponent wants to ensure no token is created, then they need to destroy it before Brimaz is declared as an attacker. The latest they can do this is in the Beginning of Combat Step. Note, that you must give them a chance to do this and cannot just rush past this step in order to attack before they can respond before attackers are declared.
Please ask rules questions in the Magic Rulings section in the future.
Like WizardMN said though, you have to give your opponent a chance to respond to changing phases. If you announce that you are moving to "declaring attackers" and they don't want to do anything at that point, then depending on if you are attacking a player and they are defending themselves will not stop the trigger but if someone is trying to stop you from getting a token, you can't skip their priority to remove your commander before you can attack.
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