Here is the full list of all 40 Last Encounter achievements.
Kill 10.000 enemies.
Have more than 10.000 credits.
Defeat the Energion boss.
Defeat the Gravitron boss.
Fully research a weapon component.
Complete a galaxy without dashing.
Have exactly 666 credits.
Fully research a 3rd slot component.
Clear all sectors before defeating the Void.
You've reached the Void.
You've reached the Nova Space galaxy.
Unlock a new pilot.
Skip any galaxy.
Unlock a new spacecraft.
Fill your third weapon slot.
Defeat the Dark Galaxy boss.
Fully research a 2nd slot component.
One of your pilots needs to die.
You've reached the Energion galaxy.
You've reached the Solarium galaxy.
You've reached the Gravitron galaxy.
You've reached the Materion galaxy.
Fill your second weapon slot.
Get some flight time under your belt.
Defeat the Void!
You've killed what was left of Lea.
Skip galaxies 100 times.
Unlock 10 pilots.
Unlock 10 ships.
Have Lea available as pilot.
Complete a galaxy without taking damage.
Complete the Dark Galaxy 70 times.
Complete Materion 60 times.
Complete Gravitron 50 times.
Complete Solarium 40 times.
Complete Energion 30 times.
Complete Nova Space 20 times.
Confront Lea with Lea.
Use 20 different passive abilities.
Collect 1.000.000 credits.