STRAIN is a 32-level partial conversion released in 1997 by the Alpha Dog Alliance. It features nine new or modified monsters through the use of DeHackEd, and a soundtrack written by David "Tolwyn" Shaw, Mark Klem, and Jon Landis.
Repackage of STRAIN v1 consisting of STRAIN.WAD and STRAIN.DEH unpacked from the original four-floppy-disk LHA archive, DOS utilities, info text files and the original LHA bundle.
On June 24, 2015, Eric Baker created and uploaded a separate "repackaged edition" of STRAIN to the idgames archive that consists simply of the contents of the original LHA archive, including the required WAD file and DeHackEd patch, with the original strain10.zip bundled with it for copyright reasons. This package was made due to the difficulty of unpacking the original release for users without either DOS, Windows, or the knowledge of DOS and Windows necessary to do so. When the files are extracted from this version, the WAD and DeHackEd patch can be loaded directly into a source port without any further user interaction.