Here is the full list of all 14 Lovely Planet achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Unlock All Stars (Mountains)
Find All Hidden Secrets
Collect All Gun Colors
Unlock All Stars (Swamp)
Drink the Sake (Swamp)
Unlock All Stars (Forest)
Find the Dagger with the Pearl Inlay (Forest)
Shoot Yourself
Unlock All Stars (Village)
Find the Hungry Samurai (Village)
Find the Graves (Village)
Visit the Shrine of Lovely Planet
Unlock All Stars (City)
Parry Projectile at Right Angles