The attack on Christophsis involved intense ground and aerial combat, initiated by the Confederacy of Independent Systems as they invaded the planet of Christophsis in 22 BBY. This occurred not long after the First Battle of Geonosis, following the conclusion of the mission to Kudo III. General Whorm Loathsom commanded the Separatist Droid Army during the land campaign. The invasion featured a prolonged siege targeting the capital city of Chaleydonia. Simultaneously, a fleet of warships led by Admiral Trench established a blockade surrounding the planet. Consequently, a Galactic Senate relief effort organized by Senator Bail Prestor Organa found itself trapped on the planet and even became a target for Separatist forces. As the invasion neared its conclusion, troops under the command of Jedi Generals Obi-Wan Kenobi and Anakin Skywalker arrived within the Christoph system.
By the time Trench's blockade was destroyed, the Separatist invasion had successfully occupied the planet; however, scattered pockets of resistance persisted, preventing a complete victory. Instead of dealing with these remaining rebels, Loathsom was compelled to divert his forces to confront the arrival of the Grand Army of the Republic on the planet's surface. As the conflict continued, an additional droid army was sent to Christophsis, with the Separatists hoping it would eliminate the Republic's forces and officially secure the planet for the Confederacy.