In its arcade heyday, Mortal Kombat was all about secrets. Players combed through the games in search of hidden content like characters and fatalities. Despite all that digging, there's one code that players' never discovered, but it would have radically changed the understanding of many of Mortal Kombat's decisions.Mortal Kombat co-creator John Tobias was on Twitter recently discussing a long-running rumor about Johnny Cage's absence from Mortal Kombat 3. What started as a simple thread discussing a long-standing rumor the popular MK character turned into a deep dive into why two fan-favorites didn't return for Mortal Kombat II.Related: Shadow Man Remastered: Trailer, Plot, Release Date & News to  Know

Mortal Kombat's struggle with memory limitations are well documented, as they're what eventually led to the series' trademark rotating cast of multicolored ninjas. Tobias explained that character omissions in the early days of Mortal Kombat were necessary because of these memory limitations, not any behind-the-scenes moves by its cast. To accommodate the new characters they wanted to add to Mortal Kombat II, such as series mainstays Jax and Kitana, some of the original cast had to go.

Tobias explained that the first cuts to the series were decided by character select audits added to the original Mortal Kombat machines. Tobias and co-creator Ed Boon actually hid an "audit code" that could be entered from the arcade's attract mode screen, allowing them to quickly see how often characters were selected. Tobias stated Boon got in the habit of checking the audit numbers whenever they found an MK machine "in the wild" and noting who the most played characters were.

Sonya Blade and Kano were the least played characters in the original Mortal Kombat, at least in the Chicago area where Midway's headquarters were located. They were cut from MK II's playable roster, although they can be seen as Shao Kahn's prisoners in the tyrant's arena. It was a learning experience for the depth of the franchise, too, as the developers were surprised to learn from those omissions that players had already become "emotionally attached" to their favorite characters.

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Fan demand helped bring Sonya and Kano back for Mortal Kombat 3, but this time Cage didn't make the cut because he was the least selected character in MK II. This led to a longstanding rumor that Cage was taken out because the actor that played him, Daniel Pesina, appeared in another game. Yet another rumor claims it was because Pesina appeared as Cage in a print ad for would-be competitor Bloodstorm. These stories often get mixed up with a time when Pesina was suing Midway over the use of his likeness in MK ports.

Razor-fisted Baraka and thunder god Raiden were also cut from the roster because they were in the bottom three of characters selected in MK II. MK 3 remains the only game in the series so far not to feature Raiden. Tobias also cleared the air on the decision to keep Scorpion, Kitana and Mileena out of the original MK 3, stating it was always the plan. They were held back for Ultimate Mortal Kombat 3, released as a free update to MK 3 offered to arcade operators as a make-good since MK 3's home console release was so close to the arcade release. Cage, Raiden and the rest of the cast would return for Mortal Kombat Trilogy, though Cage would be portrayed by a new actor, Chris Alexander. The first MK game specifically for consoles and PC, Trilogy didn't have to deal with the arcade games' memory limitations and could include anyone they wanted.

Tobias apologized to fans for the "roller coaster" that was early MK lore, which had to account for characters leaving and returning to the series from game to game. He does cheekily point out that Chicagoland MK players of the era bear some responsibility for who made it into the games. As Tobias puts it, they were "the real deciders of who lived and who died" in Mortal Kombat's early days.

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