4-LOM was a basic protocol droid who overwrote his own programming to embark into a life of crime. After reprogramming, he started to steal items from passengers on the spaceship the kuari princess, were he worked. After a while, he grew bored and left. Soon after, he met Zuckass whom he forged a friendship and became a bounty hunter. After working with Zuckass for a few years, he was enlisted by Darth Vader to hunt down Han Solo, alongside Zuckass, Boba Fett, IG-88, Dangar and Bosk. Unfortunately, Boba Fett got there first. Later he and Zuckass joined the rebel alliance and hoped to instead rescue Solo from Boba Fett, but unfortunately they failed tragically. Zuckass repaired 4-LOM but had to wipe his memory making him forget the alliance and losse any of his friendly nature, making him a cold blooded killing machine, even severing ties to his lifelong friend Zuckass, although they both worked together one more time to capture a high ranking official, but parted again afterwards.
- It's possible that 4-LOM was based on the brizzit species as they both share the same head design.
- When Kenner released the figures on him and Zuckass, they mixed up the names by calling 4-LOM, Zuckass and Vice Versa.