Here is the full list of all 31 The Legend of Korra trophies - there are 12 bronze, 14 silver, 4 gold and 1 platinum.
Got all other trophies.
Completed the highest difficulty of Pro-bending.
Won a Face-Off in a Pro-bending match.
Collected every treasure item.
Completed the game on Extreme difficulty.
Countered 100 times.
Maxed out all bending types.
Purchased 12 talismans.
Collected 10 cabbages.
Spirit-bended 200 dark spirits.
Obtained all combos.
Performed 100 Finishing Moves.
Went into Avatar State 10 times.
Got 10 knock-outs in Pro-bending matches.
Completed all tutorials.
Completed Chapter 8.
Completed Chapter 7.
Completed Chapter 6.
Completed Chapter 5.
Went into Clash Mode 10 times.
Dodged 100 times.
Completed Chapter 4.
Completed Chapter 3.
Used your first equipped item.
Completed a Naga Running sequence without hitting anything.
Entered the Collection Screen for the first time after finding a treasure.
Equipped your first item on the Korra's Room.
Bought your first item at the shop.
Completed Chapter 2.
Jumped 100 times.
Completed Chapter 1.