Mortal Kombat (Genesis)
This game has unused music.
This game has a prerelease article
The word "code" has many different definitions. The Shaolin Martial Arts Tournament is governed by a system of rules of conduct... an ethical code. The combatants respect each other as warriors, no matter what degree of hatred they have for one another... a code of honor. Another type of code could be defined as an arbitrary system of symbols or letters for transmitting messages... a secret code.
Mortal Kombat adheres to many codes, and time has confirmed that its Genesis interpretation contains two (remember ABACABB and DULLARD!)...but does it contain any unused game code?
Song #15 in the Sound Test is a track that sounds like the music of Test Your Might in the arcade version. The Genesis version uses song #16.