Sub Zero and Scorpion are the first characters I think of when it comes to Mortal Kombat. For me, it's really all about Sub Zero but his undead ninja rival sneaks in on account of being pretty much a palette swap with moves I sucked at using.
Mortal Kombat creator Ed Boon recently revealed to Game Informer that a game had been planned to center around these two characters. The spin-off was to be developed by Paradox following its work on Shaolin Monks and would have featured Scorpion and Sub Zero working together with cooperative gameplay. The title was to be called "Fire & Ice."
Unfortunately, says Boon, the project was in its early stages when axed. That's too bad. I skipped Shaolin Monks after being burned a couple of times by shoddy spin-off titles in this series but reading over some reviews is convincing me that I should give it a try.
Ed Boon Reveals The Canceled Mortal Kombat: Fire & Ice [Game Informer via GoNintendo]