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