Here is the full list of all 17 Path of Giants achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Undo 12 times in a row
Complete 12 levels without using undo
Collect ALL the coins
Find the sneaky coin in level 17
Complete Winterfest
Get unstuck after being stuck
Complete any Winterfest island without using undo
Discover the hidden treasure
Enter the hidden chamber
Find the Lantri!
Ride 30 elevators
Smash a distant pot in level 9
Get an explorer to say "Woo!"
Get onto a spinning platform that you control
Break 7 pots in 3 seconds
Boost down on an explorer
Boost up on an explorer