A clone trooper known as Bellow fought for the Galactic Republic within the ranks of the 501st Legion during the Clone Wars. In 22 BBY, Bellow, serving under the command of Jedi General Anakin Skywalker and Clone Captain Rex, participated in a mission to Benglor. The purpose of this planet-based operation was to investigate suspected activity by the Confederacy of Independent Systems. While navigating the jungle alongside Skywalker and fellow clones, Bellow came across fragments of a B1-series battle droid. His search for further evidence was cut short when a creature ambushed him and devoured him.
During the Clone Wars, a clone trooper who went by the name Bellow fought for the Grand Army of the Republic's 501st Legion in their conflict with the Confederacy of Independent Systems. Like all clone troopers in the Republic's service, he was grown and trained on the planet Kamino, using the DNA of the human bounty hunter Jango Fett. In 22 BBY during the Clone Wars, he was under the command of Jedi General Anakin Skywalker and Clone Captain Rex during a mission to the planet Benglor to investigate Separatist activity.
Skywalker, Rex, Hardcase, and another clone accompanied Bellow as he made his way through Benglor's sweltering jungle. Skywalker was on the verge of calling off the mission due to the oppressive heat, as their search for Separatists had been fruitless. Hardcase discovered a green-colored slime on a nearby tree and alerted the others, believing it to be a possible clue.
Bellow then located the head of a B1-series battle droid in a sand dune, and he jokingly told Hardcase that he had found better evidence. As the clones continued to unearth more droid parts, Skywalker deduced that they had been deliberately placed to lure them into a trap. However, before Skywalker could warn his comrades, Bellow spotted more of the slime and called out to the others.
As a massive creature burst from the undergrowth, Skywalker shouted a warning to Bellow. The creature attacked with incredible speed. Bellow only had time to turn and scream in terror as the creature ensnared him with its tongue before swallowing him whole. When Skywalker ordered a retreat, Hardcase defied the order and attacked the creature, seeking vengeance for Bellow's death. Skywalker intervened to save Hardcase, ultimately killing the creature with Rex's assistance. Rex later recounted the story of Bellow's demise to Clone Commander CC-2224 during the Separatist siege of Hisseen.
Bellow was equipped with Phase I clone trooper armor, which featured the 501st's distinctive blue markings on each arm.
The 2020 comic book Star Wars Adventures: The Clone Wars – Battle Tales 1, penned by Michael Moreci and illustrated by Arianna Florean, included a flashback scene featuring Bellow.