In the years following the fall of Emperor Palpatine at the Battle of Endor, the Imperial Remnant looked to bolster its troops through the use of droids, ranging from Battle Droids as previously seen during the Clone Wars, through monsterous War Droids of various models, to reclaimed astromech droids, retrofitted with weaponry. These so called Blastromech droids
filled a niche with their compact size and ability to fly short distances. R3-C4 was one such Blastromech serving the Empire in their fight to regain control over the galaxy.
Recipe, additional turnaround photos and a cardback can be found in my custom thread