Here is the full list of all 38 Hero of the Kingdom achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Destroy the Dark Lord.
Fight 12 battles.
Own 5,000 gold coins.
Make 25 sun solutions.
Find 300 mushrooms.
Find 60 lost crates and barrels.
Find 140 eggs.
Gather 40 sacks of night flowers.
Pick 45 herbs.
Hunt down 65 wild animals.
Catch 160 fish.
Have 350 fame.
Heal five people.
Find 12 pearls.
Find 12 treasures.
Help two ghosts.
Rest 50 times in a camp.
Gather 15 barrels of algae.
Learn an expert skill.
Hunt down 25 wild animals.
Build or repair 10 structures.
Find father.
Catch 80 fish.
Own 500 gold coins.
Find 30 lost crates and barrels.
Find 25 crayfish.
Get a boat.
Become a soldier.
Find 150 mushrooms.
Have 100 fame.
Learn an advanced skill.
Finish the water mill.
Learn three skills.
Get a weapon.
Make a barter.
Leave the home farm.
Saw 10 pieces of wood.
Get working tools.