Here is the full list of all 20 Labyronia Elements achievements.
Enter the World of Water
Defeat Elder Mistwhale in Anshar
Defeat Buchis in Anshar
Defeat Death in Anshar
Enter the World of Air
Defeat Tollan in Cindyral
Defeat Abramelin in Cindyral
Defeat Pyros in Cindyral
Enter the World of Fire
Defeat Wall of Evil in Nuterra
Defeat Zemocon in Nuterra
Defeat Crusher in Nuterra
Enter the World of Earth
Begin Your Quest
Defeat Leviathan in Aquilus
Defeat Playful Water Fairy in Aquilus
Defeat Crodin in Aquilus
Defeat Thanos in Labyronia
Defeat Andras in Labyronia
Defeat Nerubis in Labyronia