The Yllotat system, a star system situated in the Bothan sector of the Mid Rim, served as the battleground where Darth Vader launched a campaign. His objective was to dismantle the Bothan spy network that had divulged details regarding the second Death Star to the Rebel Alliance.
The name Yllotat is actually an anagram; it's a rearrangement of the letters in "totally". If you combine this with the system's name from the prior TIE Fighter mission, "Semag," you spell out the name of the company Totally Games.