Many of the people in the Netherrealm and the Chaosrealm that sounds like their talking gibberish are actually speaking backwards, in fact the actual spoken quote for each person does not match what is being said, Examples of what some of these characters are saying include (but not limited to):
- "There are many Realms,"
- "I am talking backwards, spooky isn't it,"
- "Parents of the world, There is no satanic messages hidden within the backward speech of Mortal Kombat,"
- "Play Mortal Kombat with a friend in Vietnam" (A Reference to O Pentelho (1996))" "If you can decode this then you have way too much time on your hands"
This is the first Mortal Kombat video game series ever to feature a self-fatality move "Hara-Kiri" where the player can perform this move before the winner can perform "Fatality" on them.
Goro and Shao Kahn are exclusive playable characters on the Gamecube version.
The first and only game to feature Liu Kang as an unlockable character and he was secretly kept as a surprise character.
Unlike it's prequel Mortal Kombat Deadly Alliance (2002) It is not possible in Mortal Kombat Deception (2004) to stab an opponent with your weapon in order to drain their health during a fight which was quite a big letdown due to being fun to do and looked really cool.