As an adjutant in the service of the Galactic Empire, Ssssk! was a telepathic member of a feline species. Stationed on the planet Seoul 5 in 4 ABY under the command of Imperial Captain Drezzel, Ssssk! used his telepathic abilities to monitor a pair of Imperial-funded scientists conducting research. Upon the scientists' discovery of a type of crystal found on the planet that had once served as a power source, Ssssk! detected this information through his mind-reading and promptly reported it to his superiors. Subsequently, the scientists were imprisoned, and the crystals underwent testing for potential use in weapons development.
When the smuggler Han Solo arrived on Seoul 5, Ssssk! was dispatched to locate him, leading to a confrontation between the two in a subterranean room. Ssssk! attempted a telepathic assault on Solo, but the smuggler countered with a key crystal, ultimately defeating the feline. However, Solo inadvertently activated all the crystals using the key crystal, resulting in a blinding flash that enabled the smuggler and scientists to escape, followed by a massive explosion that obliterated the city where the crystal was located, as well as the Imperial forces stationed there.
During the Galactic Empire's reign, Ssssk!, a telepath of feline origin, rose to the position of adjutant by 4 ABY. Under the command of a Human captain named Drezzel, he accompanied him and his Imperial troops to the remote planet Seoul 5. Their mission was to protect a pair of scientists, Doctor Ualp Xathan and his assistant, Fem Nu-Ar, who were funded by the Empire to conduct research on the world. These scientists had provided the Empire with charts detailing the route to the Seoul system in exchange for financial support.
On the planet, they commenced their investigation of an abandoned city constructed by the Seoularians, an extinct native species. As the scientists progressed, Ssssk! employed his telepathic abilities to monitor their progress by reading their thoughts. After translating ancient Seoulian texts, the scientists discovered that a collection of crystals had once provided power to the entire city. Ssssk! promptly reported this discovery to his superiors before the scientists could reveal it themselves. Subsequently, Xathan and Nu-Ar were confined and restrained, and the crystals were confiscated for potential weapons development.
In the year 4 ABY, the smuggler Han Solo arrived on Seoul 5, having obtained the planet's coordinates while gambling with a former Imperial scout. This scout had also provided him with one of the planet's crystals. Upon detecting Solo's landing, the Imperials on the planet informed Drezzel, who then summoned Ssssk! and Squad Three, a unit of stormtroopers. As Ssssk! approached the IF-120 landing craft where Drezzel was stationed, he overheard two stormtroopers making derogatory remarks about him. In response, he telepathically assaulted them, inflicting enough pain to leave them incapacitated on the ground. Drezzel then instructed Ssssk! and the squad to join him in tracking down the unauthorized visitor. They proceeded into the city, with Ssssk! mentally scanning the area.
Eventually, the telepath located Solo, who was concealed behind a statue of the deity Onrai. He directed the troops to Solo's location, prompting them to open fire. However, the troopers' blasterfire diverted Ssssk!'s attention, disrupting his concentration and preventing him from probing Solo's mind. This allowed the smuggler to escape through a trapdoor activated by the statue.
Ssssk! and Drezzel then descended into the room accessed by the trapdoor. Drezzel ordered the stormtroopers who had already reached Solo to cease firing, as he did not want the Seoularian crystals in the room to be damaged. Instead, Ssssk! launched a telepathic attack on Solo, who had discovered the imprisoned scientists. However, Solo amplified his own mental abilities using the crystal he possessed, which the scientists identified as the key crystal.
Empowered by this crystal, Solo successfully defended himself against the feline's assault, causing the telepath to collapse. The smuggler was also weakened by the attack and inadvertently secured the key crystal into a pedestal in the chamber while attempting to steady himself. This action activated the other crystals, causing the chamber to be flooded with light. This allowed Solo and the scientists to escape to the Millennium Falcon, Solo's YT-1300 light freighter, and flee. As they departed, a massive explosion erupted from the crystal control room, obliterating the city and much of the surrounding area.
Ssssk! was characterized by brown fur and yellow [eyes](/article/eye-legends], typical of his feline species. He was generally disliked by the Imperial stormtroopers he served alongside, who considered him Drezzel's pet and taunted him based on his feline appearance. The scientists also referred to Ssssk! as Drezzel's pet, and Solo regarded the telepath as unsettling.
Ssssk!'s telepathic capabilities enabled him to read minds and induce collapse and pain in others, which he described as a limited attack. However, he was unable to overcome Solo when the Human's mental energy was augmented by the crystal. Ssssk! also claimed the ability to reduce Humans to a non-sentient state if he desired and could mentally scan for hidden enemies, although the sound of blaster fire could disrupt his concentration and negate this ability.
Ssssk! made his debut in the eighty-fourth issue of the Star Wars comic series from 1977. The issue, written by Roy Richardson and illustrated by David Mazzucchelli, was published by Marvel Comics on June 1, 1984.