|Starting area of E1M4|
Extremal Doom is a Doom megawad by Russian level designer Mikle Ilyin that was initially released in January 2003. It features three episodes, as well as some texture and sprite replacements, several of which have been taken from Hexen.
The WAD was originally released as a modified registered Doom IWAD, which made it illegal to distribute. This led to the wad falling into obscurity for many years, with distributions typically lacking any reference to the WAD's release date or authorship. In 2006, Andrey Budko (entryway) was able to get in contact with the author of the WAD and received permission to convert it into a PWAD, allowing it to be uploaded to the idgames archive. This release also fixes bugs in the original release, including node rebuilds to avoid problems with falling through the floor.
Although the episode names were changed, the level name graphics were not.