Astrostein is a mod for registered Wolfenstein, made by Spifferaneous. It was released on April 25, 1999.
Spifferaneous made his mod in 1998 and 1999, with deep inspiration, almost obsession (according to the Read Me) with Ryder's set. 30 brand new levels are featured as three episodes were fully finished. The remaining three episodes rely heavily on the original maps. Some of these are either full copies or based on their original Wolfenstein 3D counterparts.
Most graphics have been replaced, conjuring up a definitive outer space atmosphere.
This mod was ported to ECWolf in 2015 by AstroCreep, with extra features such as brightness levels, flat textures and updated sprites. This port also includes Bruce Ryder’s demo as an extra episode. Two versions exist, one with sprites from WolfenDOOM and one with sprites from the Mac version of Astrostein. The port was later updated again with updated enemies and weapons for Astrostein ASE Special Edition.