Blood Source Campaign
"BloodSource was a campaign launched in August 1999 by Greg '\frightfan/' Enright to obtain the source code of Blood from its owners... The Blood source code was the only missing part, since the BUILD source code (the engine Blood used) was released by its creator, Ken Silverman. Even the Watcom C compiler is free now. During the campaign's lifetime, Greg obtained legal and technical information from various people, including officials from Monolith, 3D Realms and Infogrames, and Blood developers. Matt Saettler (Project Manager and Coder) and Nick Newhard (Game Designer) were particularly helpful in this quest and deserve a big thank. The BloodSource campaign gave birth to the ReBUILD project in August 2000, which in turn gave birth to the Transfusion Project in March 2001 (known as qBlood at the beginning). Greg stopped his work for the BloodSource campaign in February 2001 and passed the reins to Timothy Hale. Timothy announced the official end of the campaign in November 2001." — Transfusion page
The Blood Source Campaign (also called the Blood Source Release Campaign and the BloodSource Campaign) was a campaign launched in August 1999 aiming to convince Monolith Productions to release the Blood source code under a free software license. Blood is the only of the big three Build engine games whose source code is still proprietary. The Build engine which powers Blood is released under a pseudo-free software non-commercial custom license, and the other two major Build engine games Duke Nukem 3D and Shadow Warrior were both released under GNU General Public License by 3D Realms. Redneck Rampage was built directly on the Duke Nukem code, as was the Matt Saettler produced NAM and World War II GI and the much derided Extreme Paintbrawl.
The campaign mostly involved e-mailing people at 3D Realms, Monolith Productions, GT Interactive and the Blood development team asking for a release and asking legal questions. After long years of effort, the campaign officially died in November 2001. Instead, the former campaigners switched to rebuilding Blood on top of the free software (GNU GPL) DarkPlaces engine through the Transfusion project. This was the first of many attempted recreations on other engines, the most complete and accurate being BloodCM which was declared finished in 2016.
Components of the Blood II: The Chosen engine source code is released (that of the LithTech engine), but under a restrictive license mostly for fan modification purposes only. Some have also called for more of the Blood II source code to be released to allow for proper source ports (later LithTech code has surfaced).
The founder and long time leader was Greg Enright (frightfan), who later passed on the title to Timothy Hale (Protoplasmatic) who lead the campaign until its end (with a promise to maintain the Planet Blood campaign site for as long as Planet Blood remained online). Bloodites still campaign for the release of the Blood source code, sometimes circulating petitions and often discussing it and its prospects. There were also rumours that Monolith had lost the Blood source code, similar to what happened to Strife. Matt Saettler, the Blood project manager, is now also said to have a copy of the source code, but due to legal fears is not willing to release it at this time. In 2012 former CEO of Monolith Jason Hall stated that he also had access to the source code, but was unwilling to release it for similar reasons.
A very early version of the source code is also publicly available, though legally questionable, in the form of the full Blood Alpha; a slightly later version was leaked in January 2023. It was from this in part that a reverse engineered source port was produced in 2017 called BloodGDX. The source code to the reverse engineered source port, NBlood, based on EDuke32 is publicly available as its its various forks such as that contained in the Raze project. The code for BloodGDX was released on April 24, 2019.