What would you say are the 7 most likely 1stparties and 7 most likely 3rd parties to get in?
Excluding Octoling just because that kinda goes without saying (and could be anything), and won't touch on vague labels like "new Pokemon" or "new Fire Emblem" that don't mean anything substantial yet.
- Characters I would be surprised not to see -
Tom Nook - Arguably the most notable exclusion from the roster relative to the scale of his series and his significance within it. Animal Crossing is bigger than ever now and Smash always makes a point to add faces that casual and dedicated Nintendo fans alike would appreciate. No brainer.
Ring Fit Trainee - Sold over 14 million copies and solidifies it as Nintendo's biggest new IP since the release of Ultimate. If we're getting even just one new series in the next game, which of course we will, it would be pretty ridiculous if this isn't it.
Waluigi - Perhaps the only first party character with the overwhelming demand of previous fan favorites like Ridley and K. Rool, with neither of their respective obstacles. He's easily realizable in a playable role and he still consistently appears in games - he's part of Nintendo's cornerstone IP after all. And I'm not convinced any of the same-series competition is that high above him in the pecking order. He's THE crowd pleaser pick right now.
- Characters who could go either way -
Off the Hook OR Squid Sisters - Splatoon has gotten big enough where it could warrant a second new addition on top of Octoling. The idols are massively popular / prominent characters and could sustain a more music oriented kit which Smash has yet to tap into. Kind of a sleeper pick that I've fully committed to, feels like one of those unexpected adds that would make a whole lot of sense in retrospect.
Isaac - With the lack of BIG new Nintendo IPs otherwise and nearly two decades of sufficient fan demand, I think Isaac's chances are as good as they've ever been. Golden Sun nostalgia seems pretty hot lately with the addition of the first two games on NSO as well. Granted I don't really like to weigh NSO as anything too important, but that alongside Golden Sun and Isaac's increased prominence in Ultimate is encouraging to say the least.
Oatchi AND/OR Rookie / Shephard - This has been a big console generation for Pikmin, and I'm increasingly convinced the timing lines up nicely for some Pikmin 4 consideration. Adding on the likes of Rock, Ice or Glow Pikmin to Olimar's existing kit may end up being a bit much. So it makes more sense to just let the new additions to the series inform a new moveset - be it Oatchi himself, or Oatchi as an accessory for a more traditional captain.
Mio AND/OR Noah - Still not totally convinced, but would also be silly of me to pretend there isn't a decent enough chance. I do think it'd be a hard sell to add them both though. I've heard Noah is more efficient on his own but I'm still convinced Mio's default weapon provides a bit more of a distinct gameplay hook. I know they can technically both use it, but let's be real - Noah would mostly be his sword, Mio would mostly be her discs.
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Don't feel like getting too deep into third parties for now so I'll just give a shortlist of some characters / series that I wouldn't be shocked to see any combination of appear in base game: Chun-Li, Monster Hunter, Resident Evil, a second Sonic character, Puyo Puyo, Ninja Gaiden, Undertale. Maybe Geno.