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