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