The Fire Glyph Demos
The Fire Glyph demos (named internally as "Demo B" and "Demo C") are playable versions of the Fire Glyph area. Other than this limitation, they are identical to the same area in the retail version of Soul Reaver. Demo B is the Playstation/Dreamcast version, and Demo C is for the PC. The names were determined by looking at the room names in their truncated bigfile.dat files.
There are apparently several builds of both demo, but most have only minor differences, such as the hints given at the beginning, and the version of the actual game engine (for the PC). The only exception to this rule is the version found on the Official UK Playstation Magazine cover disc #51, which includes the entire introductory FMV from the retail Soul Reaver.
In these demos, Raziel can swim, but does not possess the Soul Reaver. However, unlike The Lighthouse Demo, he can shift planes - which is fortunate, since otherwise the puzzle would be impossible to complete.
Once Raziel obtains the Fire Glyph and uses it on a monster, the demo ends.
There do not appear to be any additional rooms contained within the version of bigfile.dat included with these demos.
The Playstation version of this demo is known to be available on the following discs: Tomb Raider II (Greatest Hits version), OPM US Demo Disc #26, OPM US Demo Disc #44, and OPM UK Demo Disc #51.
The Dreamcast version of this demo is known to be available on the following discs: ODM US Volume 5, and DreamOn Volume 8.