Y66 Division included Single Trooper Aerial Platforms, Persuader-class tank droids, OG-9 homing spider droids, and Octuptarra combat tri-droids in its arsenal. All units in the division were given enhanced self-aware programming in order to improve their efficiency in combat.
During the Battle of Christophsis, the division's B1-Series battle droids, B2 super battle droids, and tri-droids provided a second wave of attack against the Republic's 501st Legion and 212th Attack Battalion, while tank droids were used as recon scouts. Tri-droids served as mobile heavy artillery, keeping the Republic's forces from advancing. Jedi Commander Anakin Skywalker led Captain Rex and a small squad of clone troopers in a flanking maneuver against Y66 Division, successfully destroying the tri-droids and leaving the troops led by Jedi General Obi-Wan Kenobi and Commander Cody to mop up the battle droids.