If it's a direct sequel:
Base Roster/Story Characters: Kasumi, Ayane, Hayate, Ryu Hayabusa, Tina, Zack, Bass, Jann Lee, Leifang, Bayman, Helena, Leon, Christie, Hitomi, Brad Wong, Eliot, Lisa, Kokoro, Mila, Rig, NiCO, Honoka, Marie, Diego, and 2 new characters.
Unlockables: Gen Fu, Ein (Evil Clone?), Nyotengu, Rachel, Momiji, Phase 4, Maria(?)
Paid DLC: Tamaki, Kanna, other random 3rd party guest.
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If it's a reboot:
Base Roster/Story Characters: Kasumi, Ayane, Ein, Ryu Hayabusa, Tina, Zack, Bass, Jann Lee, Leifang, Bayman, Helena, Leon, Christie, Hitomi, Brad Wong, Eliot, Lisa, Gen Fu, Kokoro, Mila, NiCO, Raidou, and 2 new characters. One of them is Kelly, a nod to Zack's prototype design reimagined as an older, traditional, and well-established Muay Thai kickboxing legend that Zack partially emulates to create a style all his own.
Unlockables through Story Mode: Hayate, Nyotengu, Rachel, Momiji, Alpha-152, Genra, Bankotsubo, Naotora Ii.
Unlockables through Time Attack/Arcade/Survival/etc.: Marie, Honoka, Rig, Kasumi Alpha (essentially a rebranded character with Phase 4's moveset)
Paid DLC: Tamaki, Kanna, other random 3rd party guest.
