I've been dead busy to pay much attention but is this just... an open world dress up/Barbie doll gachagame?
I only very briefly played Shining Nikki, but like Astrogamer said, you pretty much "fight" opponents with fashion battles. The crux of the game is collecting clothes and accessories, then creating outfits. Kind of like Style Savvy, in a sense, without the shop management part.
But with Infinity Nikki, we're pretty much transitioning from a FGO-like old-style mobage to a Genshin-era modern game. If the open world design is good, I think it has potential attracting a different audience than Genshin/WW, especially within the female one.
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Re: Bang Dream, I'm getting honestly worried about the future of the global/EN server. The current event has you playing in teams of 5 players, except the netcode is even more terrible than usual and some players have received temp bans because the game thinks they are purposely disconnecting to grief others.
The technical state of the game (on global), especially the netcode, has always been mediocre, but ever since their mega-update some months ago, it's been plummeting. Players might be tempted to leave, and then there won't be enough activity/revenue from the server to justify its existence.