Here is the full list of all 51 Disgaea 4 Complete+ (Windows) achievements worth 1,000 gamerscore.
Inflict 10,000,000,000 damage.
Defeat Tyrant Overlord Baal in the Land of Carnage.
Collect all types of items.
Collect all Pirate Ship parts.
Have characters of every rank of every creatable class.
Watch every special skill animation.
Clear all X-Dimension stages.
Defeat Pringer X in the Land of Carnage.
Begins with a New Game Start a new game by selecting...New Game.
Clear Ep. 1: Rebels of Hades.
Clear Ep. 2: Prinny Wars.
Clear Ep. 3: Enter the Final Weapon.
Clear Ep. 4: Death Emizel's Death.
Clear Ep. 5: The Angel of Avarice.
Clear Ep. 6: The A-Virus Pandemic.
Clear Ep. 7: Tyrant vs. President.
Clear Ep. 8: Final Boss vs. Final Boss.
Clear Ep. 9: The Moon, Earth, and the Promise!
Clear the main story, and begin the Post-Game.
Go to the Land of Carnage and regret it.
Watch Fenrich's epilogue.
Watch Fuka's epilogue.
Watch Desco's epilogue.
Watch Emizel's epilogue.
Watch Artina's epilogue.
Defeat God (self-proclaimed).
Clear the Flashback Episode.
Clear the Fuka & Desco Show.
Win the Netherbattle Tournament.
Clear the Time Leap story.
Defeat Axel in the Post-Game and make him an ally.
Defeat Archangel Flonne in the Post-Game and make her an ally.
Defeat Raspberyl in the Post-Game and make her an ally.
Defeat Etna in the Post-Game and make her an ally.
Defeat Laharl in the Post-Game and make him an ally.
Defeat Asagi in the Post-Game and make her an ally.
Defeat Prinny Kurtis in the Post-Game and make him an ally.
Defeat Zetta in the Post-Game and make him an ally.
Capture an enemy.
Lose a battle.
Persuade by force 3 times.
Explode ten Prinnies in a row.
Open all treasure chests in the base.
Clear 30 floors in the Item World.
Max out the Rosen Queen Co. customer level.
Inflict 100,000 damage.
Destroy the Axel statue in battle.
Max out an item's level.
Train 100 times.
Get over 100,000,000 HL.
Complete all other achievements.