Here is the full list of all 9 Endless World achievements.
Evolve mercenaries for 3 times
End with the top 20 ranking in a Sprint for 1 times
Defeat 20 Mimics
Upgrade Lunar Power to Lvl 10
Collect Artifact form - Gaea's Shield
Reach Level 90
Win 10 Encounter battles
Recruit 10 Mercenaries
Make 10 purchase in Taverna