The world known as Morr Three, a planet, existed within the Amorris system. This system, in turn, was situated in the Quelii sector, found within the New Territories section of the extensive Outer Rim Territories. The Cavrilhu Pirates maintained a base on Morr Three, from which they launched attacks throughout the Amorris system. This base served as a location where the pirates could repair and upgrade their various starships.
During the Thrawn campaign, the Cavrilhu Pirates attacked a New Republic convoy and seized three IPV-1 System Patrol Crafts. These stolen ships were then transported to Morr Three for refurbishment. Subsequently, a thief of starships named Niles Ferrier arrived at the base with a delivery of power converters. He falsely claimed these converters had been ordered by the pirate Captain Zothip. However, Ferrier's true intention was to use the delivery as a cover to steal the Cavrilhu Pirates' patrol craft.
Morr Three's initial appearance occurred in the Dark Force Rising Sourcebook by West End Games. Bill Slavicsek authored this sourcebook, which was released in 1992 as part of the Star Wars: The Roleplaying Game series. Jason Fry, who co-authored the 2009 publication The Essential Atlas, verified that Morr Three's location was within the Amorris system during the development of the StarWars.com Online Companion for that book. The Essential Atlas pinpointed the Amorris system to grid square O-6.