Dif Scaur served within the ranks of the New Republic Defense Force. Initially holding the rank of admiral within the Fourth Battle Group, Scaur rose to the position of Director of the New Republic Intelligence Service following the departure of General Airen Cracken due to retirement. Despite his seemingly delicate appearance, he possessed a remarkably authoritative tone. Scaur collaborated with Alpha Blue and the Chiss in the creation of Alpha Red, a bioweapon intended to target the Yuuzhan Vong at a molecular level. Opposition arose from both the Jedi and various governmental figures, leading to Cal Omas being convinced to terminate the project following the victory that occured at Ebaq 9. After the Battle of Yuuzhan'tar and the conclusion of the Yuuzhan Vong War, Omas discreetly compelled Scaur to relinquish his position.
The character Dif Scaur was initially referenced in the original N.R.I. Reports featured on the Star Wars: Jedi Knight II: Jedi Outcast website, where he was identified as the leader of New Republic Intelligence at that time. The Yuuzhan Vong War was also mentioned. Nevertheless, both his name and references to the war were subsequently omitted from subsequent revisions of the website.