Shot Caller Trophy
As Arthur, give 15 different commands to your alliesThis can be first done during Mission 2: Operation Tonga and Mission 9: The Fourth Reich.
Each of the characters in the campaign will have special abilities. Arthur can give orders to his allies by pressing . However you need to have the opportunity to give orders, like attacking a position or a half track etc. You can't just give random orders at any time so when you see the prompt, press to give your orders, you can farm it on the same prompt or even replaying checkpoint but it's not really necessary as it should come naturally.