Looks like they aren't doing any bullshit for the gacha. It's just straight up 2.5% SSR
no soft pity, no hard pity, no 50/50, no small print.

Every pull gives you a spark. You trade 200 sparks for the rate up.
The spark doesn't reset you just accumulate it and can spend it whenever. Just like in Nikke. Right now there's no limited characters.
So any new rateup just gets immediately thrown into the general pool after release. (might be wrong will have to wait)

You also get currency for SSR / SR rolls like in Nikke that is separate. You get like 5 or 10 from events. and you can then use it to get a random SR or SSR.

So far the game is an amalgamation of the following.

>Lore = Literally CounterSide
>Visuals = Blue Archive + Star Rail
>Core Gameplay = Umamusume Roguelite + Support card system
>Battle Gameplay = Epic Seven turn based + Counterside gear system
>Gacha = Literally Nikke Gacha
>PVE Grind and Progression = Nikke + Nikke AFK
>PVP Ranking and Modes = Epic Seven. Game already has Arena PvP + Live PvP + Draft PvP

Also character progression includes:
Main Level = The usual you just use EXP stuff
Talent Level = increases base stats + unlocks skills to gain on roguelite, uses up special mats
Gear = just like c:s / e7
Dupes = increases max level and max bond, plus levels up passives. Goes upto Dupe 7 with each dupe increasing atk def hp by 2%

You can reset your whole character for a small fee. So it will be like in Nikke where you can Sync your other characters to the level of your highest 5 characters.