Here is the full list of all 43 Knack 2 trophies - there are 27 bronze, 12 silver, 3 gold and 1 platinum.
Acquired all trophies.
Equipped a combo meter and landed a 100-hit combo.
Achieved 5 stars in every Time Attack.
Achieved 5 stars in every Coliseum Attack.
Acquired 70 Knack medals.
Acquired 50 Knack medals.
Cleared a Coliseum Attack stage.
Cleared a Time Attack stage.
Learned all super moves.
Cleared one chapter on the Very Hard difficulty level.
Cleared all chapters on the Hard difficulty level or higher.
Acquired all gadgets.
Unlocked your first Crystal Knack.
Learned all basic power-up skills.
Defeated 50 enemies using parries.
Cleared all chapters on the Easy difficulty level or higher.
Cleared all chapters on the Normal difficulty level or higher.
Defeated the last boss.
Defeated all Titans.
Defeated 700 robot enemies.
Learned the Ultimate Move from Ava.
Defeated 50 immobilized enemies.
Broke the blocks of 50 enemies.
Defeated 100 enemies using Jump Kicks.
Defeated 300 enemies using kicks.
Defeated the relic monster that Xander created.
Defeated Gundahar.
Learned the Boomerang from Ava.
Defeated Rothari.
Defeated 500 goblin enemies.
Stunned enemies 50 times with sunstone bombs.
Ran 26.2 miles.
Defeated 10 enemies as small Knack.
Learned the Hook Shot from Ava.
Found 10 treasure chests.
Found 30 chests containing relic energy.
Acquired your first crystal relic.
Acquired your first Knack medal.
Completed your first gadget.
Defeated 300 enemies using punches.
Learned the Heavy Punch from Ava.
Acquired your first gadget part.
Performed your first Knack upgrade.