Someone had to do it.
We all know what Mortal Kombat is famous for, aside blood and gore, Fatalities and overpowered bosses that make us want to execute an X-Ray move in real life. Ninjas. Without Sub-Zero and Scorpion, Mortal Kombat would just be another fighting game. It would be popular, but it would probably die out before 1999, much like the Street Fighter fanbase after the live action movie was released.
If you have any ideas for ninjas, Lin Kuei, Shirai Ryu, Tengu, or just random guys in awesome suits from factions that not even Ed Boon would have heard, feel free to write them down here. Think of it as a way of saying 'Thank you, Sub-Zero, and thank you as well, Scorpion. We would buy a Scorpion/Sub-Zero doll.'