extramap.wad is a file included in Rebecca Ann Heineman's 2014 release of the source code and assets for the official port of Doom to the 3DO. It occupies a normally inaccessible slot "EXTRAMAP". It is an unfinished and unplayable level. It notably contains an excerpt from E2M5: Command Center which was removed from the Atari Jaguar version of that map, but has been retextured in the same manner as the portions which survived. Apart from that, it also contains entirely novel architecture not seen in any released level. The author and timing of the map's creation are not known, and whether or not it was ever meant to be a part of the Jaguar or 3DO releases is presently unknown.
The new architecture added to the map seems tentative and experimental. The spawning room contains an elevated platform with zombiemen and a spiral arrangement of exploding barrels which can be set off to kill them. This is somewhat reminiscent of the changes made to the opening area of E1M8: Phobos Anomaly for its console version. Outside of this area is a hallway with a distinctive "zig-zag" pattern built into the ceiling and a set of imps arranged in an arrow formation. Beyond this is an elaborately constructed area containing a demonic altar and a significant amount of enemy resistance, including multiple demons, cacodemons, and barons of Hell.
Due to the unfinished and experimental nature of this map, it has a large number of issues:
- Like some of the other maps in the Jaguar set, this map implicitly relies on missing textures being replaced with the ASH01 texture, as the Jaguar version of the game engine uses texture #0 in its internal directory when a missing texture would result, avoiding the hall of mirrors effect. This leads to an incorrect appearance if the level is loaded unmodified in a PC source port.
- There are multiple open sectors, including two of the stairs in the demonic altar area.
- The portion of E2M5 which has been cut and pasted into this map is inaccessible without application of cheat codes.
- The same area of the map has several additional problems:
- Some things are placed partway into walls.
- The door at the end of the hallway which once connected to its parent level remains as a degenerate open sector made of a single two-sided linedef with a door action assigned to it. The line can be seen through into the void, and other parts of the level are visible through it. This line can be walked through even while the door is closed, and while the door can open and close successfully, there is no apparent change to the map's geometry when it is activated.
- The teleporter designed to escape the nukage pit is non-functional, due to still being tagged to its destination sector in E2M5, which does not exist in this map.
The E2M5 section from the balcony above the nukage.
- extramap.wad in the 3DO GitHub repository.