Here is the full list of all 50 Ori and the Blind Forest achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Complete the game
A beloved bond
Fan the flames
Kill 50 enemies with Stomp
Enter Mt. Horu
Collect 200 Energy Shards
Kill 4 enemies simultaneously using Charge Flame.
Kill 500 enemies with Spirit Flame
Trick 5 enemies into killing another enemy
Find the lost corridor in the Misty Woods
Climb to the top of Nibel
Save at every Spirit Portal
Find 50% of all secrets
Earn all Efficiency Skills in the Ability Tree
Kill 100 enemies with Charge Flame
Have a close encounter
Restore the winds of Nibel
Clear the haze from the Misty Woods
Earn all Utility Skills in the Ability Tree
Escape a dangerous situation
Cleanse the Ginso Tree's Heart
Create 50 Soul Links
Kill 25 enemies using Bash to reflect projectiles
Restore 50% of all Map Stones
Restore all Map Stones
Enter the Ginso Tree
Kill 3 enemies without touching the ground
Make an unexpected friend
Cause an enemy to destroy itself
Crush a Ram with a Stomper
Discover the character in the shadows
Break open 5 shortcuts using the Charge Flame
Meet the Ancient Being
Restore your first Map Stone
Use your first ability point
Find your first secret
Complete the Prologue
Kill 5 enemies with Charge Jump
Find all secrets
Visit 100% of the map
Earn all Combat Skills in the Ability Tree
Earn all skills in the Ability Tree
Collect all Energy Cells
Collect all Health Cells
Juggle a rock 5 times without it hitting the ground
Bash off enemies 10 times in a row without touching the ground
Finish the game in under 3 hours
Double Jump 5 times consecutively without touching the ground
Complete whole game without dying
Complete the whole game without using an Ability Point