Mortal Kombat X, also known as MKX, was released to the Sony PlayStation 4 and Xbox One on April 14^th, and is also available on the PC.  Fans of the gaming franchise, which is over twenty years old, are anxiously awaiting DLC (Downloadable Content) as well as any possible new characters. 

One of the newest characters is Jason Vorhees, the slasher who wore a hockey mask in most of the Friday the 13^th films.  He is included in the MASKDMURDER Pack, which was released on April 26^th.  As of this writing, today should be the unveiling of the Klassic Pack #1, and this will feature Tremor, a brown garbed ninja and member of the Black Dragon clan who made his debut in Mortal Kombat: Special Forces, according to the Mortal Kombat Wikia. 

According to the Ecumenical News (from the Mortal Kombat Wiki) there will be a lot of Skin Packs available for players which include:

• The Samurai Pack: Samurai Shinnok, Ronin Kenshi, and Jingu Kitana
• The Ultimate Horror Pack: Vampiress Mileena, Kraken Reptile, and Pharaoh Ermac
• The Klassic Pack #1: Klassic Sonya, Klassic Liu Kang, and Klassic Kano.
• The Predator and Prey Pack: Infared Scorpion, Commando Johnny, and Carl Weathers as Dillon for Jax
• The Klassic Pack #2: Klassic Jax, Klassic Kung Lao, and Klassic Quan Chi

According to Attack of the Fanboy, a certain user on the Mortal Kombat forum received an email from EB Games Australia with the release dates for the DLC packs for Mortal Kombat X.  It is possible that the release dates might be Australian date, but since this is digital content, it is quite possible for them to be released at the same time all around the world. 

May 24^th will be the day where users can get the DLC pack HUNTERPREY, which will allow players to play as the Predator from the popular movie series.  Not only will fans get to play as the famous hunting alien, but there will be a skin on the pack with Carl Weathers as Jax. 

The last DLC for Mortal Kombat X is Klassic Pack #2, which will include Tanya, who first appeared in Mortal Kombat 4.

According to Gamerant, there might be something more to the DLC packs then just the characters.  As Mortal Kombat X was released on Steam, a lot of PC users were reporting problems with the download.  Some "inquisitive players" stumbled upon DLC packs labelled "Klassic Fatalities 1" as well as "Klassic Fatalities 2" with all sorts of characters and skins that have been showing up on the game. 

These Klassic Fatalities DLC packs are clearly meant to hearken back twenty years ago, when the original Mortal Kombat game was getting a lot of press due to its "Fatality" feature.  This was at the end of a fight, when the announcer would say "Finish Him/Her", and then winner would kill the opponent in a very brutal way.   For example, one kill involved the winner ripping off the opponent's spine, with head attached.  The Fatalities had to be performed with a special combination of buttons, giving the player an additional challenge.  As Mortal Kombat went from the traditional stand-up arcade to the console, a lot of concerned parents were disturbed by the violence.  As a result, this eventually led to the video game rating system. 

You can pick up Mortal Kombat X for the Xbox One, PlayStation 4, and PC now.  Players who are really loyal to the Mortal Kombat franchise can pick up a "Kombat Pack" promotion that is a season pass for automatically unlocking a predetermined set of DLC upgrades, which includes the four new characters and five new skin packs mentioned above.