Here is the full list of all 33 Snake Pass achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Placed Three Keystones Into The Gate
Fixed The First Gate
Fell To Your Death Near A Danger Sign
Received A Gift From Bol-Dor, Earth Gatekeeper
Received A Gift From Sog-Gee, Water Gatekeeper
Received A Gift From Cyn-Derr, Fire Gatekeeper
Received A Gift From Bloh-Wee, Air Gatekeeper
Used Snake Vision
Used Each Of Noodle's Skills
Activated A Gate Without Activating Any Checkpoints
Disturbed A Gatekeeper Idol In Every Level
Used Every Type Of Switch
Death Comes In Many Forms
Completed Every Level Without Dying
Fell From A Great Height
Used Hummingbird's Tail Lift 100 Times
Collected And Placed Keystones On The Gate One At A Time
Used Hummingbird Take-Off Points 50 Times
Used Hummingbird's Tail Lift Continuously In Paradise Path
Got A Hole In One On Crooked Canal
Completed Lazy Lagoon Without Touching The Water
Collected Two Keystones In Gatekeeper Gardens Without Touching The Floor
Death Has No Meaning To You
Pulled Every Kind Of Face
Maintained Top Slither Speed For 10 Seconds
Collected All Of Earth's Wisps
Collected All Of Water's Wisps
Collected All Of Fire's Wisps
Collected All Of Air's Wisps
Collected All Of The Gatekeeper Coins
Collected 20% Of The Collectibles
Collected 50% Of The Collectibles
You Can't Get Better Than 100%