Tranquility

Tranquility is an unnumbered location entry in the Ultima Segmentum, distinct from the numbered worlds Tranquility II and Tranquility III. It is the additional "Tranquility" that some maps of the Ultima Segmentum show. The site already treats Tranquility II, a feudal desert world held by the Mantis Warriors, and Tranquility III, which contains the Valley of the Nine Winds, in the Tranquility System.

The history of the Endymion Cluster is recorded on those numbered worlds. Tranquility II was subject to Dark Eldar, Ork pirates and cultists until the Mantis Warriors broke the power of the slave-lords. Tranquility III trained feral tribes until the Carcharodons stripped a generation of them during the Badab War. The unnumbered entry has no separate history of its own, and the sibling entry tranquility-ii already carries the alias "Tranquility".

The entry persists as a record of a leftover name and is not a fourth Mantis Warriors fief. Unofficial summaries keep it in the Ultima Segmentum, do not attribute the Badab Tranquility Campaign to it, and do not place it under the Tranquility System.