Skill? In Mortal Kombat?
"Hold block button, sometimes tap down, wait for opponent to make a move, if he gets too close jump away so you don't get thrown"
That's mortal kombat in a nutshell.
Plus it has the easiest inputs of any game... Well maybe tekken is easier, but don't tell the tekken crew that.
http://www.youtube.com/watch?v=fq54gDSOmCE
Watch his inputs. Look at all that sweet fucking button mashing he's doing and still doing the combos.
Casual game is casual.