I'm not in all honesty. They got the rights for Banjo, his music, his stage and the cameos and the Spirits. All that in itself probably cost a decent chunk of change considering, as far as I know, you have to other purchase rights to characters individually or just blanket cover which could get very pricy.
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So guys, I think I want to speculate something. This had a bit more weight before I confirmed with Sabi that Terry in no way hints at character #5 and everyone is in the dark, but here me out.
Sakurai kept mentioning souls and 'Poor soul' in the B&K breakdown. Like, four or five times pretty much back to back he said that. So many people (that I'll jokingly call normies here) immediately thought Dark Souls. My first thought? Someone else mentioned it here, but Soul Calibur.
Soul Calibur is all about poor lost souls forever clashing over Soul Edge and Soul Calibur. There are evil character who are collecting souls to get stronger, one of the mechanics is called Soul Charge, hell the legendary weapons everyone fights over have Soul in their name...HELL THE GAME HAS IT IN IT'S NAME! Even the announcer keeps talking about souls. If what Sakurai said was a hint, to me it's clearly Soul Calibur.
You remember that Japanese leak that maybe be fake now? Talking about a female character with a flying weapon? The more I thought about it, Nakoruru didn't make the cut to that: sure, her falcon can fly and she attacks with it, but it's not a weapon in the traditional sense. You know who this does work with though?
Ivy Valentine!
Her snake sword has a bunch of different stances and uses and when she whips it around in that air it is very much a lightweight kind floaty weapon. In some of the ways she uses it it actually comes apart and the pieces fly around so I think she's a good fit for both these pieces of speculation. I felt more confident when I thought Terry hinted at the next character because Terry is a fighting game character with a legacy and history, so my thoughts were that either Heihachi or a Kazama could show up or Nightmare/Siegfried but Ivy fits more than one bill here as she would fall under the two above AND the idea that Terry's inclusion could hint towards the next character...even though that's not true now.
Also, she's very much the 'Chun-Li' of Soul Calibur, if such a thing can be said since Soul Calibur is ridden with dozens of fan favorite characters. However, I would say that she is second in popularity only to Siegfried/Nightmare who, even separated, are essentially the same character. She's also female, which would satisfy the weird representation lust some of this fandom has for whatever reason. On top of that, people are wondering why Namco doesn't have a rep aside from Pac-Man. Well, other than Pac-Man being the absolute perfect rep for Namco in every possible way I can think of, maybe they are getting a new rep and we just don't know it yet!
That is all I got for now. Time to get ready for work...:/