Here is the full list of all 18 Quinterra achievements.
Kill 5 enemy units in combat encounters
Kill 50 enemy units in combat encounters
Kill 100 enemy units in combat encounters
Kill 500 enemy units in combat encounters
Kill 1000 enemy units in combat encounters
Make it through the most daunting tutorial the world has ever seen
Make it through an easy region for the first time
Make it through a medium region for the first time
Make it through a hard region for the first time
Complete a full expedition as the Lycans
Complete a full expedition as the Imps
Complete a full expedition as the Crystalians
Complete a full expedition as the Ethereals
Win your first combat encounter
Win 10 combat encounters
Win 50 combat encounters
Win 100 combat encounters
Win 500 combat encounters