While the DOS version of Powerslave uses the Build engine as noted below, the PlayStation and Saturn releases use Lobotomy's Slavedriver engine, which allows for unrestricted 3D architecture and real-time lighting similar to Quake. This is why in the Saturn and PS versions of the game you can see sloped surfaces and light coronas that aren't in the DOS version.
On January 30, 1999, Exhumed (Powerslave) was put on the infamous German index by the BPjS.
Note: Indexed products by the BPjS/BPjM are illegal to sell or make available to minors in Germany and it is illegal to advertise for it in any form. But there is absolutely no law forbidding any adult to buy such a product. The only exception is when a game was in addition also confiscated (or put on the so-called "List B" for BPjM games), but this is rather seldom the case.
In this particularly case here, Exhumed was just indexed, but not confiscated.
However, due to the fact that advertisement also means the presence of a product on the shelves of a store, the product will disappear from the public. But it can be bought in supporting stores "under the desk" (per request).
BPjS/BPjM = German Bundesprüfstelle für jugendgefährdende Schriften/Medien = Federal Examination Office for Youth-Endangering Publications/Media.
Powerslave was originally to be released under the 3D Realms label. Its working title during its stint at 3D Realms was "Ruins: Return of the Gods". Screenshots of those early days were included in Apogee's Mystic Towers slideshow (circa July 1994).
This game used and early version of the Build engine developed by 3D Realms and made popular by Duke Nukem 3d. Even though the registered version of Powerslave was released long after Duke 3d, it used an earlier version of the engine, making it technologically inferior.
The game manual does not have any installation instructions whatsoever.