Prior to Wolfenstein 3D: Third Encounter, it was necessary to patch new scenarios to the program directly using WolfEdit. Once Third Encounter and the Commercial Edition became available, scenarios were now kept as separate files, and Ewing moved to take advantage of this. He wrote a patch for WolfEdit, v1.1C, and also wrote Wolf FKEY.
By using Wolf FKEY to modify a user’s copy of First or Second Encounter, a user could now open an appropriate scenario file directly from the program by entering a command at the Title Screen. Once the player is finished, the game returns to its original state, all without having to modify the original scenario data. (Contrary to what the name would suggest, the command for doing so is actually
Cmd-Shift-9, and not any of the actual F-keys.)
Wolf FKEY was widely distributed with custom scenarios intended for play with Wolfenstein 3D: First and Second Encounters due to legal concerns with the distribution of modified versions of the game. It remained in use even after the release of WolfEdit 2, but with the release of the Wolfenstein 3D source code in 2000 and the subsequent distribution of the Commercial Edition, Wolf FKEY became largely obsolete.