Pesterminator: The Western Exterminator is a side-scrolling action platformer developed and published by Color Dreams for the NES in 1990. Players take on the role of Kernel Kleanup, the mascot of a western pest control company, tasked with saving the world. The evil super-rat Ronnie fires a "pest ray" from his moon base, unleashing hordes of mutated pests across Earth. Armed with Kernel's iconic hammer, players must eliminate pests like spiders, ants, fireflies, worms, sharks, jellyfish, and mutants across nine levels set in locations including houses, office buildings, warehouses, hotels, swamps, and even the moon. Some levels introduce new gameplay mechanics, such as helicopter piloting in Level 5, underwater exploration in Level 7, and lunar surface exploration in Level 8. During gameplay, players can check a status report showing remaining pests, and some defeated enemies drop heart icons for extra lives. The final level adds adventure elements, requiring players to find a keycard to enter Ronnie's lair for the final showdown.