Unlock 'Upgrade Simple Shot"
Unlock 'Double your turn speed'
Unlock 'Tri-shot'
Unlock 'Upgrade Tri-shot'
Unlock 'Full-Auto'
Finish level 3 without doing a direct hit to any enemy or debris. Only use bounces (on walls).
Granted if you finish level 5 without wasting a single bullet. All the bullets you shoot must hit an enemy or debris.
All the bullets you shoot must hit an "unpopped" enemy first. Zero waste. No wall nor debris nor wasted bullet. Pro-ecological achievement. Finish level 5.
Get one million points in a single game.