Here is the full list of all 13 Umbra Galaxy achievements.
Win all levels
Destroy 100 enemies
Destroy 500 enemies
Destroy 1000 enemies
Start the game
Destroy 10 generators
Destroy 30 generators
Destroy 50 generators
Destroy first boss
Destroy second boss
Destroy 10,000 enemies
Destroy 250 generators
Die for the first time