The MotherClan was a group of members of Riileb species who were believed to be descended from the First Riileb, a mythical being amongst the species. The eldest female member of the group would at the age of thirty in local years, the equivalent of 21 standard years, inherit the ClanRing, a piece of jewelry rumored to have been made by the First Riileb. The holder would rule all of Riileb society, although political infighting and trickery was common amongst the members of the MotherClan in line to inherit the ring and the heir would often be removed by other Riileb further down the line of inheritance. Tere Metallo was one such heir and was sold into slavery at the age of 25 by a who wished to inherit power instead.
The MotherClan was first mentioned in the short story "Rendezvous with Destiny" written by Charlene Newcomb which was published in 1995 in the sixth issue of the Star Wars Adventure Journal series of roleplaying supplements for the West End Games roleplaying game, Star Wars: The Roleplaying Game. It was then mentioned again in the article "Alien Encounters" by Brian Smithson in the thirteenth issue of the series published in 1997. The article was then published again in a reduced form in Alien Encounters in 1998, a collection of all the "Alien Encounters" articles compiled by Paul Sudlow.
- "Alien Encounters" — Star Wars Adventure Journal 13
- Alien Encounters