Full list of all 20 Shiro achievements worth 3,000 gamerscore. It takes around 1-2 hours to unlock all of the achievements in the base game on Xbox One.
The base game contains 10 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 10 achievements worth 2,000 Gamerscore.
Complete the "Forest" location
Die 100 times
Break the bamboo
Don't take damage in the flight section
Leave the temple
Free the Fairy
Get out of the mushroom forest
Get out of the red mine
Save the sister
Free all birds
Defeat 25 enemies
Defeat 20 enemies
Defeat 15 enemies
Defeat 10 enemies
Defeat 5 enemies
Kill one forest slime
You monster!
Slay the forest warrior
Slay one skeleton
Skeleton Squad Destroyer!