Here is the full list of all 24 Learn Japanese To Survive! Katakana War achievements.
Try 3 different types of seafood.
Unlock the power of the Crystarium
Clear the game.
Complete all 20 side quests.
Obtain the ultimate sword.
Unlock the potential of corn soup.
Complete 15 side quests.
Complete lesson 10.
Complete lesson 9.
Complete lesson 8.
Complete lesson 7.
Complete 10 side quests.
Complete lesson 6.
Maximize a character's affection level.
Complete lesson 5.
Visit the Challenge Castle.
Complete 5 side quests.
Complete lesson 4.
Complete lesson 3.
Complete a side quest.
View a character's affection event.
Complete lesson 2.
Complete lesson 1.
Maximize all character's affection levels.