New characters:
Dixie Kong: She's easily the next in line for a new DK rep, she's important, relevant and unique all in one and she could be extremely fun with a hair-based moveset making her a grappler type character almost that relies on throws.
King K. Rool: The main villain of the DK series makes a lot of sense, plus we need more villain and more heavyweights too, it's a win-win situation. He'd also have a pretty unique moveset with a bunch of crazy gadgets at his disposal.
Impa: One of the few reoccurring characters in the Zelda series with a lot of potential to be a unique character, she doesn't have too much but an agile magic user isn't something we have right now.
Ridley: Once again, more villains and more heavyweights, win-win. He would also be a very unique fighter with his tail, claws, teeth and even wings all at his disposal.
Medusa: Another villain and another classic villain too as the main antagonist of the first Kid Icarus which I think makes her somewhat iconic. She'd also be a fun fighter and could be the first female heavyweight (Unless Samus counts) which would be nice to see a bit of diversity in that regard. She has her staff and a bunch of attacks which could come straight from uprising like lasers and poisonous gas and tons more that could easily translate into a moveset.
Bandana Dee: The dee is next in line for a new Kirby character with a unique spear based playstyle which would be interesting to see, he'd also be very projectile heavy.
Takamaru: Upgrading from his assist trophy role in Smash 4 Takamaru makes a very unique fighter with his Katana with lighting quick attacks where he unsheathes and sheaths his blade with every swing.
Krystal: Krystal brings a unique Bojutsu fighting style with her attacks, combine that with her elemental attacks and she can be a very unique fighter, Many of her attacks could come straight from Adventures too so coming up with a moveset wouldn't be hard and with a semi-confirmed future she could very well get in.
Fiora: With her dual blades, drones and general agility, Fiora would be a very fun character, with a tension mechanic straight from her games and a variety of arts at her disposal, once again, a moveset isn't hard. Plus with recent appearances like Project X Zone 2 Fiora could very well keep showing up, she's still one of the least likely characters on this whole thing though.
Elma: The (practically) main character of the recent Xenoblade Chronicles X makes a lot of sense to show up and with her dual blades and dual guns that she can switch between at will she has good reason. Plus a sequel is only a matter of time at this point.
Isaac: The main character of the the Golden Sun series of games, although not exactly relevant the franchise should still be represented and Isaac would be a fun character with his earth based Psynergy attacks.
Chibi-Robo: Using his play as a makeshift whip, Chibi-Robo would be a very fun character however his future as of right now is unknown, regardless the series should be represented.
Inkling: Splatoon was a smash hit and Inklings have a lot of potential to be unique characters with a variety of weapons including guns, rollers, snipers, a bunch of different bombs, a wall of ink and so much more. Add in a territorial ink mechanic which allows them to swim across the map in seconds and a few moves from the mii gunners and you have a very unique character.
Knuckles: The rival to Sonic and one of Sega's most iconic characters, Knuckles does make some sense being a brawler. He'd have a mix of power and speed and potential unique mechanics like gliding, digging and climbing on walls which could easily make him a unique character.
Rayman: Another icon of the gaming industry, with his plethora of moveset potential and the decent relationship between Nintendo and Ubisoft I don't think he's too out there at all, plus he represents one of the biggest companies in the industry right now.
Lara Croft: She's easily one of the most iconic gaming characters to exist right now so she makes sense to add, especially if they wanted to appeal to western fans too. With athleticism and gunplay Lara could make a very fun and unique character and given Nintendo and Square's recent relationship them getting a second character isn't too far fetched, plus who knows? Maybe we could get Tomb Raider games on the NX.
Returning characters:
Wolf: Wolf is a fan favourite and given his importance to the Star Fox games it's mind boggling why he isn't in Smash 4.
Ice Climbers: The only thing holding them back was technical limitations, with that no longer being an issue they should have no problem returning.
Snake: Another extremely iconic character and although issues with Konami still exist, I say it's worth it to get this fan favourite back.
Pokemon Trainer: They're the best representation for the Pokemon series and Charizard being solo still annoys me, plus those technical limitations are gone too.
Cut characters:
Roy: I just don't think he's important enough compared to the other Fire Emblem characters of which I think there are too many.
Doctor Mario: He feels worthless, he's literally Mario in a Doctor's coat, I can't justify him being in at all.
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