Here is the full list of all 51 Disgaea 5 Complete achievements.
Condition：Obtain all other trophies.
Get a Game Over. "Let this humiliation fuel your strength."
Conquer the Carnage Dimension. (Defeat Carnage Dark) "This is the ultimate power!"
Deal over 10,000,000,000 damage. "Blow 'em away!"
Max out an item's level. "Annihilate enemies with the weapons you've modified!"
Obtain an epic item. "This is sweet!"
Obtain the legendary weapon in the Item World. "Only the chosen one can equip it..."
Pass a bill by Paying Up 100,000,000 HL. "I hope it's worth it!"
Force the Dark Assembly to approve a bill. "In the end, it's all about the 'Aye.' "
Perform 20 combos. "Finish 'em off all at once!"
Get 50 One Time Bonuses. "You're taking all the bonuses!"
Obtain more than 10,000,000,000 HL. "So, whatcha gonna blow it all on?"
Reach the goal in the Chara World on Super Overlord difficulty. "It takes a lot of gaming to get this far."
Enter the Carnage Dimension. "We can't lose to the overwhelming power of Carnage!"
Unlock all character classes. "Master every path possible!"
Level up to Lv 9999. "It's just a destination, not the final stop!"
Pass a bill that gives you a Trophy. "Yes, you earned it."
Discover 100 Netherworlds. "Find new frontiers!"
Defeat Proto Darkdeath in the Item World. "Wh-Who is this guy...!?"
Achieve a population of 100 in the pocket Netherworld. "The pocket Netherworld has gotten pretty crowded."
Clear Final Ep.: Dedicated to the Precious People. "I'll save her, no matter what!"
Clear Ep. 14: Seraphina's Secret. "A girl in love is invincible!!!"
Clear Ep. 15: The Ultimate Skill. "Excellent..."
Clear Ep. 13: The Two Killias. "...Yeah, farewell."
Clear Ep. 12: Unbridled Killia. "The one who leaves destruction in his wake."
Repel a Netherworld in the Item World. "Just another day for you and me in the Netherworld."
Clear Ep. 11: Netherworld Extinction. "They are all irreplaceable."
Clear Ep. 10: The Memorable Special Sweet Curry. "Our...beloved daughter..."
Clear Ep. 9: The New Power. "Guuurrryaaahhh!!!"
Clear Ep. 8: Past Struggles Part 2. "Master!!!"
Eat curry for 100 days straight. "They're demons so they're fine. Please don't try this at home."
Experience the effects of the hot springs in an Item World Mystery Room. "No peeking on the girls' side."
Clear Ep. 7: Past Struggles Part 1. "Bro!"
Nullify all Geo Panels with a Geo Chain of 5 or more. "Find the trick and erase all of them at once!"
Clear Ep. 6: The Sixth Warrior. "Dance of the Bristle Grass!"
Call your Netherworld for the first time. "If you call it...it will come."
Capture 100 prisoners. "Round them up!"
Reach the goal in the Chara Word. "Congratulations!"
Clear Ep. 5: The One Who Controls Death. "Kill and Recycle!"
Activate Revenge Mode 100 times. "Your hatred makes you powerful!"
Clear Ep. 4: Yellow, Rabbit, and Curry. "I want curry, I want curry, I want curry, I want curry..."
Watch 20 skits. "Enjoy the daily lives of demons."
Jump 1,000 times at the base. "Once you hop, you just can't stop."
Hit allies inside the base 100 times. "Be gentle."
Clear Ep. 3: His Name is Zeroken. "A silver white shadow that creates a storm..."
Complete 20 quests. "We'll accept any quest."
Clear Ep. 2: Demon General. "Madam Seraphina, hooray!"
Clear Ep. 1: Prelude to Vengeance. "The story of rebellion starts now!"
Completely fill the Bonus Gauge. "Take everything!"
Perform a Combo Skill for the first time. "This is the power of bonds!"
Use an Overload skill for the first time. "Watch closely for the power of an Overlord."