Have You Tried the Hidden Fatality on 'Mortal Kombat 9'? Here's How it Originated says Creator
Mortal Kombat 9 may be a fairly old game, but this Hidden Fatality may resurrect it again for fans. There is a Hidden Fatality that was revealed by one of "Mortal Kombat's" creators, Ed Boon, particularly found in the 2011-released game, "Mortal Kombat 9.
Source: techtimes.com