During the initial period of the Clone Wars in 22 BBY, Jedi General Anakin Skywalker spearheaded an investigation into Confederacy of Independent Systems operations occurring on the planet Benglor. Skywalker, accompanied by his clone troopers from the esteemed 501st Legion, uncovered remnants of Separatist battle droids. However, their exploration was interrupted by an aggressive creature that caused the demise of a trooper known as Bellow. Skywalker then instructed Clone Captain Rex to safely guide the troopers away from the danger. Later, Rex chose to return and provided assistance to Skywalker, ultimately contributing to the creature's defeat.
A venture to the planet Benglor was undertaken by Anakin Skywalker, Captain Rex, and members of the 501st Legion. As they traversed a forest, the oppressive heat became a common complaint. Hardcase stumbled upon a viscous substance, hoping it would offer insight into the activities of the Confederacy of Independent Systems on the planet. Subsequently, Bellow discovered the head of a B1-series battle droid, with other soldiers also locating fragmented droid components. Bellow encountered more of the viscous substance, unaware of the large quadruped lurking behind him. Anakin activated his lightsaber and issued a warning to Bellow, but his efforts were in vain. The creature seized Bellow and devoured him.
Anakin commanded a retreat, however, Hardcase recklessly charged towards the creature, only to be effortlessly thrown aside. Anakin then directed Rex to lead his men to safety while he remained to rescue Hardcase. As the quadruped prepared to deliver a fatal blow, Anakin utilized the Force to halt the creature's advance, enabling Hardcase to escape. Following Hardcase's departure, Anakin confronted the quadruped, but was subsequently knocked against a tree. Anakin hurled his lightsaber at a different tree, causing it to fall and crush the creature. Anakin nonchalantly walked away, only for the creature to recover and lunge towards him. Before it could reach Anakin, it was shot down by Rex and his fellow clone troopers. Rex suggested that Anakin throw his lightsaber at the creature's leg, which successfully subdued it. As Rex and Anakin departed, Anakin expressed that he regarded Rex and the other troopers as more than just clones.
At a later time after the mission, a siege unfolded on the planet Hisseen between the forces of the Galactic Republic and the Confederacy of Independent Systems. Clone troopers were defending a village against an onslaught from the Separatist Droid Army. Jedi Generals Anakin Skywalker, Obi-Wan Kenobi and Plo Koon arrived to provide assistance to the clone troopers, successfully repelling the attack. The Jedi then departed to locate Count Dooku and Asajj Ventress, but first sent a transmission requesting reinforcements for the clones.