Here is the full list of all 45 Omega One achievements.
Killed a total of 50 boss ships
Reached the level cap of 50
Killed a total of 25 boss ships
Reach Level 20
Unlocked Ship: Wasp
Unlock weapon: Flak
Killed a total of 10 boss ships
Unlock weapon: Plasma
Killed a total of 5 boss ships
Killed A total of 1000 Ship Enemies
reach level 10
Unlocked Ship: Tonic
Unlocked Ship: Hornet
Unlocked Ship: Galactica
Unlock weapon: Needler
Unlock weapon: Cannon
Reach wave 20
Killed A total of 500 Ship Enemies
Reach wave 15
Pickup a total of 100 power up drops
Killed A total of 250 Ship Enemies
Score 20000 points
Reach level 5
Unlock weapon: Spreader
Killed A total of 100 Ship Enemies
Reach level 2
Unlocked Ship: Razor
Reach wave 10
Posted your first online score
Died for the 1st time
Killed your first boss
Score 9000 points
Killed A total of 50 Ship Enemies
Score 5000 points
Pickup a total of 10 power up drops
Reach wave 5
Score 1000 points
Pickup your first power drop
Check out SSS on Youtube
Check out SSS on Facebook
Check out SSS on Twitter
Viewed the high-score table
Played 1v1 for the first time
Won a 1v1
Started the game (for stats purposes)