Prove your self in battle. Battle through 3 waves with no deaths.
Get a streak of 50 kills
Complete 10 waves in the same game
Rescue 15 engineers in 1 game
Progress past wave 3 then kill a boss ship with a smart bomb
Complete 2 waves in the same game
Complete 1 Wave
Complete 5 waves in the same game
Get a streak of 100 kills
Get a streak of 150 kills
Achieve 1000 Kills
Achieve 5000 Kills
Rescue 5 engineers in 1 game