you probaly have to connect with somebody and internet
maybe it could be on psp, but so far its only on xbox 360 and playstation 3.
in the player select screen press R a small screen should pop up and say SELECT ARENA
Nope
Yes you can get Mortal Kombat for the PS Vita. The game is available for Preorder for December 25 2012. The price for the USA PS Vita game is $39.99. The game will be rated M