Crossing Acheron is a single-level PWAD designed by John W. "Dr. Sleep" Anderson. As part of their 10 Years of Doom feature, Doomworld named it one of the ten best WADs of 1994. At least four versions of the map are known to exist: * Version 0.0 (ACHERON.WAD), released June 10, 1994. * Version 1.666 (ACHERON6.WAD), released September 23, 1994. * Version 2.0 (ACHERON2.WAD), released October 12, 1994. * Version 2.2 (ACHRON22.WAD), released July 5, 1995.