MPSod, also known as MP's Spear of Destiny Add-on, is a map set released on August 31, 1999. It was made by Maarten Pinxten and is noteworthy for it's high quality in mapping.
This was Pinxten's second map set for Spear of Destiny. His first was 1998's Spearmpixsod which likewise featured mapping of high quality.
Certain levels in MPSod follow the original Spear of Destiny's layout (e.g. level 11 is still a castle level with cubic design) while still taking liberties (mutants in level 7, etc.)
It is playable in SDL as it is only a map set.