Here is the full list of all 14 Boom Brothers achievements.
Customise the appearance of your soldier
Spray your Steam avatar during a game
Kill a bird
Send a chat message
Get 100 kills with the SMG
Get 100 kills with the Sniper
Get 100 kills with the Shotgun
Run a player over with a jeep
Be killed due to being outside of the map for too long
Throw down a utility box
Get 50 kills with a bomber plane
Get 50 kills in a fighter plane
Get 50 kills in a tank
Get 10 kills with grenades