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Perdition's Crossing was a 2,400 kilometer stretch of gulch of desert on Mar Sara. Because of the wave-band anomalies of the area, vector-balance equipment would not function and communications would be scrambled, if they go through at all. This made travel by land difficult and travel by dropship nearly impossible. The Confederate Science Corps theorized that the anomaly was due to the rare crystal formations in the gulch, but it was never confirmed.
Due to the limited communications in and out of the crossing, it was considered to be one of the most lawless areas of space. Slavers such as the Mazor gang were common, and preyed on the scientists who could come to the gulch to try to study its minerals.
As a Confederate marshal, Jim Raynor was tasked with transporting three prisoners, T-Bone Smalls, Rodney Oseen, and Marduke Saul, across this stretch to El Indio Prison. The entire trip would take about two days, but on the way Raynor encountered a transport raided by the Mazor gang. Raynor gave his prisoners an offer that if they helped him free the slaves they had, he would pretend they died in the firefight and let them go. Rodney and Smalls betrayed him, but Marduke kept to his word and the Mazor gang was destroyed. Raynor finished the trek with Smalls and Rodney, but kept his word and let Marduke go.