Here is the full list of all 30 Disgaea PC achievements.
Completed Final Episode "What Lies Beyond the Battle"
Completed Ep. 1 of Etna Mode "Super Dimensional Etna"
Completed Final Episode of Etna Mode "Chronicles of Etnarnia"
Cleared Extra Stages "Cave of Ordeal"
Defeated the Extra Boss "Priere"
Defeated the Extra Boss "Marjoly"
Defeated the Extra Boss "Baal"
Defeated all EX bosses!
Defeated the Extra Boss "Item King"
Defeated the Extra Boss "Item God"
Defeated the Extra Boss "Item God 2"
Killed 1,000 enemies!
Performed your first transmigration
Performed 10 transmigrations
Obtained the Dream Hand!
Obtained the Hyperdrive!
Completed Ep. 10 "Angels, Demons, and Humans"
Killed 500 enemies!
Completed Ep. 5 "Etna's Secret"
Defeated the Extra Boss "Item General"
Obtained 10,000,000 HL at the end of battle
Killed 100 enemies!
Obtained Total LV 10,000
Obtained Total LV 1,000
Obtained Total LV 5,000
Completed Ep. 1 "Prince of the Netherworld"
Dealt 100,000 Damage!
Dealt 10,000,000 Damage!
Obtained Total LV 100
Obtained 1,000,000 HL