The Spirit Glyph Altar would have granted Raziel the ability to cast the similarly cut Spirit Glyph. Until 2020 it was unknown what the Spirit Glyph altar would have looked like or where the area would be located. The closest resembling area released to the public was one of Robert Chang's test rooms which included coiled symbols throughout the chamber suspected to be representing the Spirit Glyph. Ultimately the Soul Reaver alpha discoveries in 2020 exposed the forge.
The Spirit Glyph and it's accompanying altar was originally developed for inclusion in Legacy of Kain: Soul Reaver. Like other cut material its presence was noted in several prerelease articles including issue 19 of PSM. Lengthy delays to the release of Soul Reaver meant that much of the latter portion of the game was cut and remaining loose ends repurposed to fit the rest of the game. As the last and most powerful glyph altar the Spirit Glyph suffered this fate and its removal became public knowledge though its intended whereabouts remained unknown.
Artist Robert Chang's portfolio was updated in 2003 with images of some test rooms created for Legacy of Kain: Soul Reaver. These test rooms notably bore a layout which bore hallmarks of both the Reaver forges and the Glyph altars and notably featured the symbol of the unused Spirit Glyph, leading to speculation that this was the Spirit Glyph altar or an early version of it.
Discovery and exposure of the Soul Reaver alphas in 2020 finally exposed the location and design of the Spirit Glyph altar, revealing that the altar was an area that had in fact made it into the game but it had been repurposed to serve as a location to gain a Health power-ups - with the ”Mrlock” fountain area found in the Human Citadel in the retail version originally designed as the Spirit Glyph altar. Originally the area had been placed just off “hub b” in a cave that is occupied by a large fire in the retail version. The ”hub b area” itself originally contained the entrance to the Turelim Clan Territory rather than the Oracle's Cave - hence the ”Mrlock” coding.
The original puzzle of the altar involved Raziel activating a switch to trap himself in the top room with an advancing Melchahim and luring it on to the target pad where its souls would be released to empower the Spirit Glyph. Much of this functionality is still present in the alphas but requires coded activation.
- Close examination of the Glyph altars - including the Spirit Glyph altar - reveals that most have a common basic design, with a number of thin square pillars marking out the area. This feature was key to identifying the area, although it is notably absent from the Stone Glyph Altar. This feature is also present in Robert Chang tests which also resemble the layouts of the Reaver forges, potentially suggesting they may have been the progenitor of both.
- Robert Chang's potential early Spirit glyph altar designs appear to lean heavily on the Spirit Forges of Blood Omen. Notably these required some kind of blood sacrifice to operate. In the same manner both the Spirit Forge and Spirit Glyph altar discovered in the Soul Reaver alphas appear to require a sacrifice to operate - one or both may also indicate the intended use of Possession to get around this.