Here is the full list of all 44 Mages Initiation: Reign of the Elements achievements.
Kill 1,000 enemies.
Kill 500 enemies.
Finish the game with all 4 classes.
Earn all Earth class Bonus points.
Complete all class-based side quests with optimal outcomes.
Optimally complete the Earth side quest.
Earn all Air class Bonus points.
Optimally complete the Air side quest.
Find and read all books and notes.
Finish the game with max XP / score.
Max out all your stats.
Earn all Fire class Bonus points.
Kill one of each monster type.
Win the maximum number of Demon's Deal rounds.
Optimally complete the Fire side quest.
Kill 100 enemies.
Kill only the bosses (no regular monsters).
Beat the game without equipping any extra gems or items (after the initial tutorial).
Earn all Water class Bonus points.
Complete the severed circle story branch.
Pick all mushroom clusters in the forest.
An ally survives.
Make a red delivery to the Greencaps.
Optimally complete the Water side quest.
Complete the game.
Defeat the Big Bad.
Both allies survive.
Complete the third trial.
Reject a dark deal.
Extinguish the Redcaps' camp fire.
Find all three "Tear" class brooches.
Beat both Mage sparring partners.
Earn your third spells from the Sphere of Knowledge.
Complete the second trial.
Ele'port to each pillar stone location.
No sacred avian was harmed.
Win a hand of Demon's Deal.
Acquire one of each drink type at the tavern.
Return a borrowed item.
Kill 50 enemies.
Earn your second spells from the Sphere of Knowledge.
Complete the first trial.
Spare a tainted life.
Earn your first spells from the Sphere of Knowledge.