So far the only known characters are as follows.
* Scorpion
* Liu Kang
* Kung Lao
* Sub-Zero
* Sindel
* Ermac
* Reptile
* Kitana
* Johnny Cage
* Jade
* Mileena
* Nightwolf
* Cyrax
* Noob Saibot
* Smoke
* Sektor
* Sonya
* Jax
* Kano
* Stryker
* Shang Tsung
* Baraka
* Kabal
* Raiden
And these 2 are dlc characters I believe, hope this helps!
* Sheeva
* Quan Chi