Here is the full list of all 20 EARTH'S DAWN achievements.
Learn all skills
Clear all free missions
Save the planet from the threat of invaders.
Clear Mission - Motherstar
Clear Mission - Icicle Tower
Defeat a total of 2000 enemies
Clear Mission - Chilly
Clear Mission - Breakthrough
Clear mission - End of the Line
Clear Mission - Demonic Mountain
Obtain S Rank in 60 missions
Clear Mission - Empty Death
Clear mission - Missing Person Search
Clear Mission - Star-devouring Snake
Clear Mission - Underground Invasion
Clear Mission - Mocking Laughter
Clear Mission - Assault Strategy
Clear Mission - Watch for the Fists
Clear Mission - Advance into Darkness
Clear mission - The Beginning of the End