Alpha and Beta Versions
Prototype versions of Soul Reaver were the main source of concrete information on the material removed from the game, following their recovery in the first two decades of the 21st century. In particular, the 1999-02-16 build contains nearly-complete versions of The Turelim Clan Territory, The Undercity and The Temple, The Elemental Reaver Forges, a few early sections of The Mountain Retreat, and additional areas within the Silenced Cathedral (discussed in Alternate Silenced Cathedral Areas and The Pinnacle of The Silenced Cathedral).
The Lost Worlds Collection
The following ten prototype versions of Soul Reaver for the PlayStation are known to exist, and possessed by Lost Worlds staff:
While other prototype versions of the game were created in-house at Crystal Dynamics between 1998 and 1999, none of them are known to have survived into the 21st century. If you are in possession of a prototype which is not on this list, please Contact us. Versions of the game from March/April 1999, or any time in 1998 are especially of interest.
Prototypes Which Aren't
The non-English PAL releases of Soul Reaver have build dates before any of the English versions (1999-07-05 and 1999-07-06, versus 1999-07-15 for the UK PAL release version, and 1999-07-27 for the NTSC release version). This has caused copies of them to be miscategorized as prototypes in a few cases.