The Yahk-Tosh were a sentient species of slug-like beings originating from Xolu, a planet situated within Hutt Space. It was theorized that they shared a distant ancestry with the notorious Hutts. Physically, they resembled slugs, possessing six sturdy arms used for locomotion, and their hide was a murky green color and scaled. Distinctive features included four slender horns protruding from their heads and pointed snouts filled with rows of sharp, serrated teeth.
Similar to the Hutts, the Yahk-Tosh exhibited immunity to Force-based mind tricks. In addition to their native homeworld, they held dominion over Far Pando, another planet within Hutt Space, while acknowledging the authority of the Hutt Grand Council. A notable Yahk-Tosh Lord, Gar-Oth, achieved notoriety by conquering Princess Lourdes' homeworld, until she, aided by Jedi Knight Yoshi Raph-Elan, brought about his demise.
Resembling slugs, the Yahk-Tosh were a sentient species thought to be distantly related to the Hutt species, sharing certain physical characteristics. Like Hutts, they possessed resilient, green hides, a singular foot for movement, and a similar facial arrangement with two eyes and a mouth containing a tongue. However, unlike Hutts, they had six arms, each ending in three digits, which they used for locomotion, scaly skin, teeth within their mouth and four horns growing from the top of their heads. Their blood was red, and they secreted slime. At least one member exhibited yellow eyes. Like Hutts, they were resistant to mind tricks employed by Force-sensitive individuals and possessed some degree of telepathic ability, sufficient to control certain droids. Despite their size, they were surprisingly swift, capable of matching a human's pace, and possessed remarkable strength.
The Yahk-Tosh originated on the planet Xolu within the galaxy's region known as Hutt Space. This territory was governed by the Hutt species and their leadership body, the Hutt Grand Council, to which the Yahk-Tosh pledged allegiance. Initial exploration of the region occurred between 15,000 BBY and 8000 BBY, with Hutt Space expanding to encompass Xolu by the time of the Great Sith War spanning from 4000 BBY to 3996 BBY. Within Hutt Space, they also held control over the pleasant agrarian world of Far Pando. Both Xolu and Far Pando were situated on the Pando Spur hyperlane, connecting them to Hollastin and Near Pando, other planets within Hutt Space.
By 31 BBY, a Yahk-Tosh warlord named Gar-Oth had established an empire. However, in that year, he met his death after successfully invading a small planetoid with a droid army and attempting to force a marriage with its ruler, Princess Lourdes, who fatally stabbed him with the assistance of a Jedi named Yoshi Raph-Elan. As of 137 ABY, Xolu and the Yahk-Tosh were still considered part of Hutt Space.
Gar-Oth, a Yahk-Tosh, rose to prominence as a crime lord, wielding control over a small empire through his droid army. Seeking to expand his dominion, Gar-Oth and his forces invaded a small planetoid in a star system near his empire. The droids suppressed local resistance, resulting in numerous deaths, including the planetoid's king. Upon securing control, Gar-Oth imposed a series of laws, enforced by his GX1-series battle droid units. These included a curfew, with violators facing death, designated as punishment code 62719. Any attempt to rescue a citizen from this fate constituted a violation of decree code 352719, also punishable by death. Seeking legitimacy, Gar-Oth arranged to marry the deceased king's daughter, Princess Lourdes. The droids continued to kill civilians until the princess agreed to his proposal. While preparations for the marriage were underway, Lourdes was guarded by battle droids within a castle, monitored by probe droids.
As Lourdes remained captive, Gar-Oth's impatience grew. When mystics foretold an individual who would thwart the marriage, he moved the date forward to coincide with his engagement ball. Arriving at the ball with two Jilruan servants and a droid named Goliath, his wedding gift to Lourdes, he declared that they would marry immediately to avoid the Foreseen. To ensure her compliance, he dispatched battle droids to villages with orders to kill the inhabitants should Lourdes refuse. However, upon Gar-Oth's insistence on an immediate wedding, Lourdes' servant revealed himself to be her husband. In truth, the Human was a Jedi Knight named Yoshi Raph-Elan, whose starfighter had been shot down by the Yahk-Tosh's droid starfighters. Enraged, Gar-Oth attacked Yoshi with his bare hands, invoking the planetoid's royal law permitting combat to the death between wedding suitors. Gar-Oth's droids aided him, while his living servants were barred from interfering. When Yoshi's attempt at a mind trick failed, Gar-Oth realized his Force-sensitivity and, further enraged, telepathically commanded Goliath to kill Yoshi and Lourdes. Yoshi engaged the droid, while Lourdes attacked her fiancé with a sword taken from one of the Jilruans. Gar-Oth overpowered Lourdes and began throttling her, prompting a Jilruan to offer to kill her with his dagger, but he was stopped by Lourdes' servant, Skeeter. To Gar-Oth's surprise, Lourdes stabbed him with a second sword concealed beneath her robes, killing him. Shortly after, Yoshi destroyed Goliath, whose collapse crushed most of Gar-Oth's attendants and droids. Following the Yahk-Tosh's death, Lourdes' people reclaimed the planetoid, and Yoshi returned to the Jedi Order.
The Yahk-Tosh made their debut in 2001 within the comic book Star Wars (1998) 27, an issue of the Star Wars: Republic comic series published by Dark Horse Comics. Penned by Doug Petrie, the comic featured Gar-Oth as its primary antagonist. While the comic did not explicitly identify Gar-Oth's species, it referred to his language as Yahk-Tosh. The species received its official designation within an entry on Princess Lourdes in De Agostini's 128th issue of The Official Star Wars Fact File, authored by Andrew Darling, Matthew Harvey, Liz Holliday, and Iain Lowson in 2004. Subsequently, the species and Gar-Oth himself were featured in The Complete Star Wars Encyclopedia, written by Pablo Hidalgo and Stephen J. Sansweet in 2008, which established their potential relationship to the Hutts. Their homeworld and control of Far Pando were documented in The Essential Atlas, authored by Daniel Wallace and Jason Fry in 2009 and published by Del Rey. Wallace further elaborated on Gar-Oth in two blog posts concerning the Atlas, identifying the Yahk-Tosh's attendants as Jilruans, a detail not explicitly stated in the atlas itself.