Here is the full list of all 31 Fairy Knights achievements.
A beginning of the journey.
Digi joined the party!
Elisa joined the party!
Fire magic earned!
Earth magic earned!
About Aru!
Forest magic earned!
Wind magic earned!
Defeated Taringus!
Earned the legendary sword!
Have seen the ending of the game!
Earned a weapon!
1st battle completed!
1st Level up!
1st Skill level up!
1st Item bought!
1st weapon upgraded!
Have revived!
2 Combo!
3 Combo!
4 Combo!
5 Combo!
Wow! Several Combo!
First magic!
Perfect warrior!!
Full level warrior!
Fire wizard!
Water wizard!
Earth wizard!
Forest wizard!
Wind wizard!