Here is the full list of all 21 Brodefence achievements.
Kill 20 enemies
Kill 50 enemies
Kill 100 enemies
Kill 200 enemies
Kill 500 enemies
Play for all the characters
To die 1 time
To die 3 times
To die 5 time
Pick up 3 bonus
Pick up 10 bonus
Pick up 30 bonus
Survive 2 minutes
Survive 4 minutes
Survive 6 minutes
Survive 10 minutes
Survive 15 minutes
Survive 20 minutes
Kill the boss
Use two air strikes in a row
Explode on your own mine.