Tranquility

Tranquility is a leftover Ultima namesake pin, not Tranquility II the Mantis Warriors feudal desert or Tranquility III the Valley of the Nine Winds already researched in the Tranquility System. This existing row sits outside that well.

The Endymion Cluster story lives on the numbered worlds: II took Dark Eldar, Ork pirates, and cultists until the Mantis Warriors broke the slave-lords; III trained feral tribes until Carcharodons stripped a generation in the Badab War. This un-numbered cube is the extra Tranquility some maps drop in Ultima. Sibling tranquility-ii already holds the alias Tranquility.

Tranquility still matters as a leftover name, not a fourth Mantis Warriors fief. Unofficial summaries keep Ultima Segmentum, refuse to paste the Badab Tranquility Campaign onto this row, and do not re-parent it into tranquility-system.