I just figured out the last character in the roster.
It has to be someone from the Starfox series, because if you look, if Wolf or Krystal appeared under Falco it would push Lucario to the right which is under the Pokemon series, and Lucario would push Ness under Ike and Ness would push Sonic under Snake which is the 3rd party row, and Sonic would push Bowser on the very bottom row directly under Peach with the Mario series, which would then push Wario directly under Yoshi which is under the Mario Series also, and Wario would push Toon Link directly under Ganondorf which is directly under Legend of Zeld series, and that would push R.O.B. directly under Ice Climbers with series' with only one character in the game, then that moves Olimar directly under Dedede in the kirby series (but that has no significant to my theory) and that pushes captain Falcon under Wolf or Krystal in the starfox (this also is insignificant to my theory), which pushes Jigglypuff directly under Lucario in the Pokemon Series, and that pushes Lucas directly under Ness in the Mother 3 series, and finally that moves the random character at the very bottom left corner.
if you could understand that, because I'm sure it's hard to understand. The last character is Krystal or Wolf for anyone that doesn't already know.