Mortal Kombat II is an unlicensed port of Mortal Kombat made by Hummer Team. Both Kart Fighter and AV Bishoujo Senshi Girl Fighting, which were released later, use an earlier version of this game's engine.
Despite the title, this game is actually a port of the first Mortal Kombat. This was likely done as a form of selling the product as a sequel, a common trait with unlicensed NES games. While the game is mostly faithful to the original game graphics-wise, some features were cut from the game. These include fatalities and blood which are found only in Mortal Kombat II Special. Also Goro is the same size as the other characters, probably due to the NES's limitations.