The news about this broke some time ago, but Set Side B is only a few months old at the moment and we weren’t around then. It’s still worth mentioning though!
Ed Boon put secret codes in a number of his games to allow him to check on individual machines while out in the public. He revealed his code for Mortal Kombat II some time back, which is listed on The Cutting Room Floor. The code is entered entirely with the 1P and 2P Block buttons: P1 Block 5 times, P2 Block 10 times, P1 Block 2 times, P2 Block 8 times, and P1 Block 2 times. The timing is tight, so keep trying.
One way to remember part of the code is in the menu’s name, the EJB Menu. The E and B of that stand for Ed Boon. E is the 5th letter of the alphabet, J is the 10th, and B is the second, and those are the number of button pressed needed for the first three parts of the code.. The whole code would thus be EJBHB. Using initials as part of a code seems to have been part of the culture at Bally and Williams at the time. A number of pinball games have hidden displays that can be called up from attract mode if you press buttons as if you were entering a developer’s initials in the high score screen.
The EJB menu offers a lot of information on how a machine has been performing on location! It’s much like the operator’s menu, but with even more options! You can even call up the ending for any character, would certainly would have made any kid who knew that code back then the star of the arcade.
Of particular note is, a couple of the items in the menus are red herrings. The developers loved taunting kids by putting fake hidden features in the operator menus. “Shawn Attacks” is one of them (there is no character called Shawn in the game); “Kano Transformations” is another (Kano is not playable in MKII).
Other EJB menu codes:
Mortal Kombat 1, it’s 1PB x 5, 2PB x`10, 1PB x 2, 2PB once, 1PB x 2, 2 PB x 3, then 1 PB x 4. The page notes that, converted to letters, this code would be EJBABCD.
In Mortal Kombat 3, it’s 1PB x 5, 2PB x 10, 1PB x 3 (it’s EJC this time!), then 2PB once, 1PB x 2, 2PB x 2, 1PB x 3, and 2PB x 3. EJCABBCC. This code also works in Mortal Kombat 3 Ultimate.
The Cutting Room Floor does not list a EJB code for Mortal Kombat 4. Smash T.V. does have a code for a developer’s menu.