Here is the full list of all 15 The Tower Of Elements achievements.
Collected 20000 Mana Point in Total
Unlocked 10 Mages
Upgraded the Tower 20 times
Unlocked 5 Mages
Collected 4000 Mana Point in Total
Got 1300 Points
Got 1000 Points
Made 200 Combo
Upgraded the Tower 10 times
Unlocked 1 new Mage
Got 500 Points
Made 100 Combo
Upgraded the Tower to maximal level
Collected 45000 Mana Point in Total
Unlocked all other achievements