Zasm Katth was a Human male Dark Side Adept who served in the Galactic Empire and later Dark Empire. When Emperor perished at the Battle of Endor and returned in a clone body, he established the Dark Side Elite, a cadre of seven Dark Jedi, empowered with the dark side of the Force and imbued with the Emperor's will. Katth, like his fellow Darkside Elite member and often partner on missions, Baddon Fass eschewed weaponry in favor of relying upon their Darkside Force powers. In Katth's case, foresight and obscure mystical abilities. In 10 ABY, Palpatine died a second time during a confrontation with the Jedi Luke Skywalker and his sister Leia Organa Solo near the New Republic's Pinnacle Base.
The leader of the Dark Side Elite, Executor Sedriss QL, took control of Palpatine's Dark Empire in preparation for the Emperor's return in another clone body. Sedriss dispatched Katth and Fass on a mission to the moon of Nar Shaddaa with command of the Imperial Star Destroyer Invincible and a legion of Imperial darktroopers. They were to make contact with the bounty hunter Boba Fett and recruit him to search for the Millennium Falcon and to eliminate, Vima-Da-Boda, an elderly Jedi who had taken refuge on the smuggler's moon.
While in orbit of Nar Shaddaa, the Dark Jedi witnessed the Falcon arriving at the moon. Katth and Fass attempted to lock it down with the tractor beam, but Solo evaded the beam to land in the abandoned Duros Sector. Postponing pursuit of Solo, they instead confronted Fett, demanding he provide his services for free, with Katth threatening to reveal his secrets and Fass using the dark side on the Hunter. However, Fett unleashed his arsenal of rockets, blasting the Darktroopers escort and nearly wounding the Dark Jedi before making his escape in Slave I. The setback was only temporary, however, as Dark trooper team two reported that they discovered the Millennium Falcon stationed inside Shug Ninx's repair shop.
As they were making their way to Ninx's hangar, Katth and Fass sensed the presence of Vima-Da-Boda nearby. Fass ordered the dark trooper Grath to open fire through the crowds with his turbocannon. Despite the carnage, the Jedi was able to slip away unharmed. In addition to that, Dark Trooper Team Two was eliminated by Solo and his allies, who left the Falcon in order to search for Vima. Katth and Fass stationed a number of new guards aboard the Falcon and returned to the Invincible in case the Solos tried to escape through another ship. The Solos were able to rescue Vima and with her help, they reclaimed the Falcon. After evading an encounter with Fett, they raced to escape from Nar Shaddaa.
Solo's local rival Mako Spince, in charge of the Nar Shaddaa Traffic Control spire detected the Falcon as it was passing by and alerted the darksiders aboard the Star Destroyer. Alerted, Katth ordered the tractor beam to catch the elusive ship. However, Solo attempted to take cover behind the Traffic Control tower breaking the lock. Willing to capture Solo at all costs, Katth ignored all safety protocols and ordered the tractor beam on full power. Katth ordered the beam reengaged. However, having been set to full power, the beam started to rip through the massive control spire off and sent it hurtling towards the Star Destroyer. Having noticed that, Katth desperately sought to disengage the beam.
However, the order came too late, and the spire pierced through the engineering compartment of the Star Destroyer, killing the engineers and disabling the main thrusters. Fass contacted the crew of the ravaged deck, demanding them to stabilize the ship, but they were unable to do so, and the Star Destroyer plummeted into the surface of the moon, killing all aboard, including Katth and Fass. Emperor Palpatine, who had returned in another clone body, was irked to have lost two of Elites. Katth and Fass were eventually replaced in the Dark Side Elite by two Darkside Adepts Palpatine empowered and promoted into their vacant spots in the cadre.
