Here is the full list of all 41 Hyperdimension Neptunia Re;Birth2: Sisters Generation achievements.
You played so much, everyone now agrees that Nepgear is a good main character, too!
Cleared all Stella's ☆ Dungeon levels.
Obtained a total of 100 million Credits.
Discovered 200 Plans.
All characters have attained Level 99.
Histoire joined the party.
Watched the Holy Sword Ending.
Watched the Conquest Ending.
Watched the True Ending.
Defeated the hidden boss, Delphinus.
Cleared Chapter 7.
Kei Jinguji joined the party.
Cleared Chapter 6.
Mina Nishizawa joined the party.
Watched the Planeptune Ending.
Watched the Human Ending.
Watched the Lowee Ending.
Fought 500 battles.
Watched the Lastation Ending.
Watched the Leanbox Ending.
Chika Hakozaki joined the party.
Performed an 80-hit combo.
Watched the Normal Ending.
Cleared Chapter 5.
Rom's and Ram's HDD versions have been powered up!
Inflicted over 100,000 points of damage.
Uni's HDD version has been powered up!
Cleared Chapter 4.
Nepgear's HDD version has been powered up!
Cleared Chapter 3.
Cleared Chapter 2.
Fought 100 battles.
You have met Rom and Ram.
Created your first Game Disc.
You have met Uni.
Cleared Chapter 1.
Made use of Stella's ☆ Dungeon for the first time.
Used the Remake System for the first time.
Engaged in your first random encounter.
Created your own original combo setup.
You began your adventure.