Here is the full list of all 51 Disgaea 4: A Promise Unforgotten trophies - there are 42 bronze, 5 silver, 3 gold and 1 platinum.
Complete all other trophies. You have obtained all the trophies.
Collect all of the Pirate Ship parts.
Collect all items (excluding grades). Now aim for completing all the grades, too!
Enforce discipline 100 times.
Clear all of the X-Dimension maps.
Explode ten Prinnies in a row.
Watch all of the special skills.
Inflict 10,000,000,000 damage.
Defeat Pringer X: Roar in the Land of Carnage.
Unlock all Evil Symbols.
Visit the Land of Carnage.
All ranks of all job and monster classes can be created through Character Creation.
Increase an item up to LV 300.
Defeat Zetta in the Post-Game and make him an ally.
Defeat 100 Pirate Crew members in the Item World.
Defeat Asagi in the Post-Game and make her an ally.
Steal 10 Rare and/or Legendary items.
Defeat Laharl in the Post-Game and make him an ally.
Defeat Prinny Kurtis in the Post-Game and make him an ally.
Open all chests at the base from Episode 1 to Post-Game.
Train an ally up to LV 9999.
Accidentally destroy Axel's statue in the Mystery Room.
Give 50 bribes.
Conduct your first Reverse Pirating.
Defeat Etna in the Post-Game and make her an ally.
Persuade by force three times. Demons should always resort to violence!
Defeat God (self-proclaimed) and watch the ending.
Inflict 100,000 damage.
Get over 100,000,000 HL.
Open 100 treasure chests.
Max out the Rosen Queen Company customer level.
Defeat Raspberyl in the Post-Game and make her an ally.
Clear 30 floors in the Item World.
Cancel 1,000 battle actions.
Defeat Archangel Flonne in the Post-Game and make her an ally.
Defeat Axel in the Post-Game and make him an ally.
Watch Emizel's epilogue.
Throw and capture an enemy character in the base panel.
Watch Desco's epilogue.
Watch Fuka's epilogue.
Watch Fenrich's epilogue.
Clear the main game and unlock the Post-Game.
Watch Artina's epilogue.
Clear up to Episode 7 in the main story.
Conduct your first Map Edit.
Defeat an ally character.
Clear up to Episode 3 in the main story.
Fight five battles with the "Classic" display option. Pixels still rock!
Reincarnate for the first time.
Get a Game Over from having your party get defeated.
Watch the opening anime. Enjoy Disgaea 4!