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