Frost
Sonya

every fighter that was playable and make a dream match MK game

Nitara!!!!
also:
Frost
Rain
Sonya
Sheeva
Reptile

Kung Lao and Kitana are the big ones. Sektor, Fujin, and Kintaro would be pretty sweet as well. But it doesn't really matter, most everyone will probably eventually be brought back, if this game is any indication. If they brought back my Tanya, I'm sure you'll get your Rain eventually.

I would drop
Liu Kang
Darrius
Tanya
I would bring in
Smoke
Noob Saibot
As seperate characters
Kitana
Sektor
Rain
Kung Lao

Kano
Shao Kahn (as a playable)
Reptile
Motaro
why are so many people saying rain!!!

BRING BACK RAIN DEFINITELY LOL

I would make the Witch (who flys past the moon on the bridge stage) a playable character.She would be just like witch Jade Fox in Crouching Tiger.Double flawless would trigger her to fly from the moon right up to the bridge where she fights you then and there.If you beat her she becomes playable.
Maybe she in already...

Ninja Reptile
Kintaro
Reiko
Sektor
Smoke
Kai

Here's who I bring back:
1. Sonya
2. Cage
3. Mavado
4. Frost
5. I'll leave this postion vacant until I think of someone else.

Shang & KUNG LAO but if i had 2 pick 1 Shang

If I were Ed Boon and I had the chance to pick the returning characters that have not been mentioned so far I would choose alot of classic characters.
Kung Lao - I feel that Kung Lao should be in this game because he is a great character to play as and now that Liu Kang has returned from the dead I would like to see Kung Lao's perspective on that.
Johnny Cage - Johnny Cage should be in this game because he is a very fun character to play as and I like that character's attitude towards evil. Johnny Cage had been fighting with the rest of the good guys since the very first Mortal Kombat game so I would include him in this game so that I would be able to please fans and show other fans of Mortal Kombat that Johnny Cage is a decent character.
Sonya Blade - I would include Sonya Blade in this game because she had developed into a grand character. Sonya is an icon to female fighters in Mortal Kombat and she is a lead fighter on the side of good. Sonya had conflict with the Red Dragon and with the return of the Black Dragon, Sonya has alot of opponents to battle. Sonya would also focus on defeating Onaga.