Here is the full list of all 48 The Adventure of NAYU achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Release the ninja outfit.
Release all outfits.
Collect 47 achievement stamps.
Release the witch's outfit.
Release the spearman outfit.
Unlock 35 items from Lugh's information shop.
Release the cook's outfit.
Knock down 3 GuBee's kings.
Defeat the GuBee's King.
Visit 50 areas.
Unlock 21 items from Lugh's information shop.
Maximum damage exceeds 99999.
Increase the adventurer level to 300.
Knock down 20 boss-level monsters.
Increase the adventurer level to 200.
Maximum damage exceeds 9999.
Visit 25 areas.
Collect a cumulative total of 100000 shards of stars.
Unlock 7 items from Lugh's information shop.
Knock down 100 monsters.
Activate the game for 60 minutes.
Collect 50 pieces of cheese.
Update your high score on the Road to Cheese.
Collect 10 pieces of cheese.
Collect 30 pieces of cheese.
Collect 23 achievement stamps.
Increase the adventurer level to 100.
Start endless mode
Complete the story
Release the guardians of the Forgotten metropolis.
Informed Shiro what you want.
Go into fever mode 10 times.
Collect a cumulative total of 10000 shards of stars.
Defeat the cave boss.
Discovering the Forgotten Forgotten capital.
Knock down 50 monsters.
Encounter the researcher in the cave.
Out of the woods.
Strike 300 times.
Activate the game for 30 minutes.
Meet Suzu and become friends.
Defeat Rye in the woods.
Defeat Lev in the woods.
Activate the game for 15 minutes.
Defeat the bear in the meadow.
Clear the first area of the story.
Got your first shards of the star.
First time in fever state.