Here is the full list of all 30 Sayonara Umihara Kawase achievements.
Play everything in the Sound Gallery.
View everything in the Illustration Gallery.
Clear all routes on Survival Challenge.
Clear Survival Challenge.
Play Survival Challenge.
Use all characters.
Acquire 45 backpacks.
Watch all Stage Tutorials.
Play your own Replay 10 times.
Watch the Stage Tutorial of a Stage you've cleared.
Clear all doors.
Unlock all Stages.
Clear Tadpole 2.
Catch a Tadpole.
Fail a Stage 50 times.
Clear Crab 2.
Clear Balloonfish.
Fail a Stage 20 times.
Browse the Sound Gallery.
Browse the Illustration Gallery.
Acquire 30 backpacks.
Clear Crab.
Clear Sayonara UmiharaKawase +.
Clear Tadpole.
Acquire 10 backpacks.
Clear the second door in a Stage.
Acquire two backpacks at the same time.
Check all Walkthrough Tips in the Gallery.
Acquire a backpack.
Fail a Stage while holding a backpack.