Here is the full list of all 40 BoxesWithGuns achievements.
Kill 100 enemies
Finish 10 games without hitting the wall
Finish 1 game without hitting the wall
Submit a score to the leaderboards.
Survive a song without destroying an enemy
Survive a song but destroy not more than 3 ememies
Lose a game without losing a box
Check out the ranks
Start the game
Find and submit a bug
Kill 1 000 enemies
Kill 10 000 enemies
Kill 100 000 enemies
Kill 1 000 000 enemies
Lose a game in 5 seconds
Play at least 5 hours
Lose 50 boxes
Lose 100 boxes
Lose 250 boxes
Lose 1 000 boxes
Upgrade a weapon 10 times
Upgrade a weapon 100 times
Upgrade a weapon 1 000 times
Upgrade a weapon 5 000 times
Buy 5 weapons
Buy 10 weapons
Buy 100 weapons
Buy 1 000 weapons
Total Playtime 40h
Move your mouse 10 kilometers inside the game
Move your mouse 20 kilometers inside the game
Move your mouse 50 kilometers inside the game
Collect 10000 Nuggets
Collect 50000 Nuggets
Collect 75000 Nuggets
Collect 100000 Nuggets
Collect 150000 Nuggets
Collect 250000 Nuggets
Collect 500000 Nuggets
Collect 1000000 Nuggets