Here is the full list of all 25 Solune achievements.
Complete all 50 puzzles in the main game.
Beat the game.
Enter the secret Puzzle Mode.
Have your pet dragon obtain the ultimate element.
Learn the truth of what happened to Kenzan's parents.
Obtain the Fire element for your pet.
Help fully rebuild Tenton into a bustling city.
Obtain the Wind element for your pet.
Obtain the Shadow element for your pet.
Obtain the Water element for your pet.
Recruit Striager (and Kenzan).
Obtain the Ice element for your pet.
Obtain the Lightning element for your pet.
Bet on the Imp in the Parwan Monster Races, and win.
Hatch a Dragon Egg.
Defeat Kenzan as Vaster in their first encounter.
Defeat both of the brothers who robbed Kandaria Castle.
Defeat Elrion in your first encounter.
Recruit a certain secret character.
Reach Rank 10 in the Parwan Arena.
Enter the secret Developer's Room.
Defeat Sol in his prison.
Find every treasure in the game, then go and show the Treasure Hunter in Tenton.
Beat the game, getting the 'good' ending.
Defeat the memory of the King of Dragons.