You need to master specific combo moves and button sequences. Each character has their unique fatality techniques that you can learn through practice and exploration in the game.
Yes, Mortal Kombat started as a comic. Its unique story and characters caught the attention of fans and led to its growth into various mediums. The comic's influence can still be seen in the current iterations of the Mortal Kombat franchise.
Not really necessary. It depends on your personal interest. If you're a die-hard Mortal Kombat fan, you might enjoy it for the extra storylines and character development. But if you just want to know the basic game plot, you can skip it.
Mortal Kombat wasn't initially a comic book. It made its debut in the world of video games and gained huge popularity there before branching out into other areas such as comics and movies.