It was just in my google search! I am not sure. What is Neptunia about? is it a music game
Erm. Complicated.
It has the main series which are turn based RPGs. But theres a ton of spin offs. There's the first trilogy and their remakes the Rebirth games. Then the last main series game which was VII (Victory 2).
After this there are a ton of spin offs. I can just list them all, main series and spin offs. And what systems.
Main series:
Hyperdimension Neptunia (PS3)
Hyperdimension Neptunia mk2 (PS3)
Hyperdimension Neptunia Victory (PS3)
Megadimension Neptunia VII (in Japan, Victory 2, idk why English changed it to VII to make it seem like "7") (PS4, PC, Switch)
Remakes:
Hyperdimension Neptunia Re;Birth1 (PS Vita, PC-Steam, sometime soon on Switch)
Hyperdimension Neptunia Re;Birth2 Sisters Generation (PS Vita, PC-Steam, sometime soon on Switch)
Hyperdimension Neptunia Re;Birth3 V Generation (V Century in Japan, again idk why the change) (PS Vita, PC-Steam, sometime soon on Switch)
Basically the same games as Neptunia, mk2 and Victory in that order.
Spin-offs (Will be out of order since theres quite a few):
Hyperdimension Neptunia PP Producing Perfection (PS Vita)
Hyperdimension Neptunia U Action Unleashed (PS Vita, PC-Steam)
Neptunia Virtual Stars (PS4, PC-Steam)
Neptunia x Senran Kagura Ninja Wars (PS4, Switch, PC-Steam)
Hyperdevotion Noire Goddess Black Heart (PS Vita, PC-Steam)
Megatagmention Blanc +Neptune VS Zombies (PS Vita, PC-Steam)
Cyberdimension Neptunia 4 Goddesses Online (PS4, PC-Steam)
Super Neptunia RPG (PS4, PC-Steam, Switch)
Megadimension Neptunia VIIR (PS4, PC-Steam) (Same as VII but has VR aspect and is said to be lower quality so it gets side game treatment)
Superdimension Neptune vs Sega Hard Girls (PS Vita, PC-Steam)
Neptunia Sisters vs Sisters (PS4, PC-Steam, Switch, Xbox soon)
Neptunia Game Maker R:Evolution (PS4, Switch, Xbox soon)
Phew. That was a lot! So, basically theres a lot of commentary in gaming stuff like the console wars, personifications of consoles, game companies, etc.
Most of them are RPG but some branch to action rpg, music sims, tactics games, etc.
It's a fun series and really can jump into any of em cuz theyre mostly self contained except for a few.
Being: Neptunia mk2/Rebirth2 > Neptunia Victory/Rebirth3 > Neptunia VII
after that its really whatever lmao
Though Sis vs Sis is better after plaaying the first 2, and Game Maker after VII.
So yeah, if you have any questions feel free to ask!