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