Soul Calibur: Nightmare
Mortal Kombat: Sub-Zero
Those two would stand out the most to me. It's all about being unique, correct? Or at least something special that Superbot can work with. So they'd have a higher chance I'm sure. Then again, lately it's starting to look like it's all about marketing future games.
"Exit the stage. Your act is over." - Vergil
"Come on, come on, come on, come on, come on! Now die!" - Albedo
Ah, here's something. Apparently at the MLG Summer Championship, they're doing a sub-tournament with All-Stars being one of the games there, along side Borderlands 2 and Dust 514.
And one of the bigger, actual championships there are Mortal Kombat and Soul Calibur V, both being done on the PS3 versions.
That, and the fact that PAX(August 31) is days away after MLG's summer thing(August 24-26) we'll most likely have character reveals near the end of August, most likely with 2 first party characters and 2 third party characters, particularly one from MK and one from SC if this ties in with that tweet in the OP.
My guesses are Scorpion and Ivy, the former since he was considered by Ed Boon to be in this game back in the "Title Fight" days, and Ivy since she's the poster character for SC, being in all the SC games except for Soul's Edge. In fact, I think she could be the 3rd female Paul Gale's been talking about in his hints.
I hope it happens at some point. It's gonna be sweet if both franchises are present in this game but I'm not expecting too much. As for the question itself:
- Mortal Kombat: Scorpion is more likely obviously but Sub-Zero is a fine choice as well. Can't go wrong either way.
- Soul: Nightmare or Siegfried. My pick would be Yoshimitsu though.
Maybe this is nothing, but on Twitter, I see the @HeyPlaystation account (its an official Playstation account) tweeting this
Maybe Sony has a choice to make between these franchises and this is Sony's way of asking the fans which character they would want to be in the game? I personally dont want any of them in, if I wanna play a fighting game with them, I'd go play their game.
Ezio ,Scorpion, Nightmare FTW
Crash Bandicoot from Twinsanity for PSABR ! I hope.