Mortal Kombat did indeed appear on the NES, if you count Hong Kong pirate carts.
Wolfian: Either you’re talking about a Game Genie code, or you’re misremembering and thinking of the Genesis version. The Genesis MK blood code has to hold the record for “Fastest Leaked Cheat Code in a Console Game.”
Down, Up, Left, Left, A, Right, Down on the Options screen? (That’s been umpteen jillion and five years ago, and I like MK2 better anyway.)
brianjedi: Sort of. That code is more of a general cheat code. The blood-only code is ABACABB on the “code” screen in the intro.
One more nitpicky thought: the traditional Russian folk song used in the Tetris part of the medley is the A-song from the Game Boy version. The A-song from the NES version* was Dance of the Sugarplum Fairies.
*The Nintendo NES version of Tetris, that is. Tetris was a big part of the Nintendo-Atari war. Long story, but good one.