Here is the full list of all 29 Windlands achievements.
Collect all crystals in Jungle On Normal
Collect all crystals in City On Normal
Collect all crystals in Sky On Normal
Collect all crystals in Sky On Hard
Finish game on Normal
Finish game on Hard
Finish the Sky Swing Challenge
Finish the Sky Playground
Finish the Sky Swing Challenge in Under 5 Minutes
Finish the Sky Playground in Under 5 Minutes
Collect all crystals in Jungle On Hard
Collect all crystals in City On Hard
Collect all tablets in Sky
Collect all tablets throughout the game
Collect all crystals in City On Easy
Collect all crystals in Sky On Easy
Collect all tablets in City
Finish game on Easy
Finish the City Wall Jump Challenge
Finish the City Playground
Finish the City Wall Jump Challenge in Under 4 Minutes
Finish the City Playground in Under 7 Minutes
Collect all tablets in Jungle
Finish the Jungle Swing Challenge
Finish the Jungle Playground
Finish the Jungle Swing Challenge In Under 2 Minutes
Finish the Jungle Playground in Under 5 Minutes
Collect all crystals in Jungle On Easy
Get to the end portal of Tutorial