Mortal Kombat sort of blew up, didn't it, in a bad way. All that violence and gore and edge got everyone excited, then the sequel put all that gore into a really very nice game, before the series exploded and showered two decades with disappointment and live-action television and so very many palette-shifted ninjas. Pleasantly that streak ended in 2011 with a solid display of man-mutilating in the Mortal Kombat reboot. Come 2015 we'll be smashing bones and tearing off heads again, as Mortal Kombat X has been announced.
This is one of those 'announce before E3 so people know we exist and we don't get lost in that horrible week of horriblness' dealies, so publishers Warner Bros. don't have too much to say about or show of the game right now. One fighting people will return and we'll get some new violent sorts too, each coming in variations which play a bit differently. The announcement also mentions adding "a persistent online contest where every fight matters in a global battle for supremacy."
And that's about all we'll know until E3 comes--heaven help us--next week.
Developers NetherRealm Studios do say they have "an all new graphics engine" in MKX but we've all learned our lessons about assuming announcement trailers aren't pre-rendered, haven't we? Or believing that finished games will look as pretty as their E3 'gameplay' trailers, for that matter.