This sound is from Kai - Mortal Kombat Gold - Character Sound Effects (Dreamcast)

The following is a list of games in which crossovers appear in either the form of a cameo of any kind, a guest character, or the theme of "crossover" in general in a video game itself. These may exist as a gimmick if two separate games in question are developed by the same company.
See also: and List of video game remakes and remastered ports.