Alright, so based on some of the more recent information (portal destroyed, Raiden dead), we now know that nobody from Earthrealm can get into outworld to help the fight. But we've already seen a few earthrealm folk confirmed, so this leaves some loose ends.

Let us do some storyline speculation;

Kenshi - At the end of DA, supposedly he got a royal beating from Mavado, and then goes back to Earthrealm with Sonya, Jax, and Cyrax, so how did he get to outworld again? Is it possible he never got rescued by Sonya, and thus never made it back? If so, how did he survive after Mavado beat him up so bad? Did he and Mavado actually fight then? And what about Mavado? How did he get back? Did the Special Forces actually capture him? Maybe they did but left Kenshi and Ermac saved him, not Sonya. Thoughts?

Bo Rai Cho - Taught Kung Lao how to beat down Shang, and then went back to earth with him. So how can he still be in outworld if Kung Lao went back? Maybe he decided not to go after all? Maybe Kung Lao didn't win and actually got beaten or killed, hence Liu Kang's return? Thoughts?

Sub Zero - Frost turned on him, but ended up screwing herself, so Subby carry's her back to Lin Kuei and gets thanked by Raiden. And yet somehow he's still in Outworld, and Frost is not? Does his medallion give him some interdimensional powers, so he just came back on his own? He's obviously still got it, so Frost didn't steal it. Maybe he sent her back with the other good guys and stayed behind because of Sareena? Maybe he ran into Scorpion again? Thoughts?

Sektor (non-confirmed) - Was last sighted in japan with his own clan of cyber ninjas. How on earth did he get to outworld? Did he somehow follow Sub Zero's way in? Did one of the bad guys summon him up? Who would ally with the Cyber Ninja that's turned on everyone else so far?

Undead Liu Kang - MKDA shows that apparently if you cut Shang Tsung real bad, souls fly out of him, but how did Liu Kang get a body (zombie form)? Vogel said Liu Kano didn't happen, so it's unlikely Kano turned on the DA, so could it have been Kenshi who claimed Shang's life? Who else has a sharp enough weapon? Kung Lao obviously didn't beat the souls out of him in his ending.

How about Kabal? Kira? Ben? Nightwolf? even Smoke? Lots of Earthrealm inhabitants who somehow made it into outworld without a portal. Any thoughts?

-F.