Achieve a combat-free experience for 2 minutes
Start a match and shoot some missiles. Float back down to the spawn platform and wait 2 minutes. Once the 2 minutes is up, fire some more missiles and you will hear a voice say “Peace breaker”. The trophy will unlock after this. You will need to count this time yourself as there is no way to know in game. It is best to do this with a second controller so you do not get killed.