Here is the full list of all 30 The Legend of Korra achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Completed all tutorials.
Collected 10 cabbages.
Spirit-bended 200 dark spirits.
Completed the game on Extreme difficulty.
Went into Avatar State 10 times.
Collected every treasure item.
Completed Chapter 7.
Purchased 12 talismans.
Completed the highest difficulty of Pro-bending.
Completed Chapter 6.
Completed Chapter 5.
Maxed out all bending types.
Completed Chapter 4.
Countered 100 times.
Completed a Naga Running sequence without hitting anything.
Obtained all combos.
Won a Face-Off in a Pro-bending match.
Got 10 Knockouts in Pro-bending matches.
Completed Chapter 8.
Performed 100 Finishing Moves.
Went into Clash Mode 10 times.
Dodged 100 times.
Jumped 100 times.
Completed Chapter 3.
Used your first equipped item.
Entered the Collection Screen for the first time after finding a treasure.
Equip your first item in Korra's Room.
Bought your first item at the shop.
Completed Chapter 2.
Completed Chapter 1.