X-1 was a type of poison. It was sold by the propetior Zlarb at their shop on the Imperial capital world Coruscant. Between 3 ABY and 4 ABY, the assassin Ochi of Bestoon visited Zlarb to acquire poisons for his upcoming mission to assassinate Emperor Palpatine's Royal Guards for the criminal syndicate Crimson Dawn. While at the shop, Zlarb mentioned X-1 as a poison avaiable to Ochi, though he ultimately did not purchase the poison.
X-1 was mentioned in the current Star Wars canon in the second issue of the 2021 comic miniseries Star Wars: Crimson Reign. The issue was written by Charles Soule and published by Marvel Comics on February 2, 2022. In the Star Wars Legends continuity, the poison X-1 was first indirectly mentioned in The Hutt Gambit, a 1997 novel written by A. C. Crispin as the second installment in Star Wars: The Han Solo Trilogy. It was later identified by name in Rebel Dawn, the third installment of the trilogy that was also written by Crispin and published in 1998.
X-1 was mentioned in the current Star Wars canon in the second issue of the 2021 comic miniseries Star Wars: Crimson Reign. The issue was written by Charles Soule and published by Marvel Comics on February 2, 2022. In the Star Wars Legends continuity, the poison X-1 was first indirectly mentioned in The Hutt Gambit, a 1997 novel written by A. C. Crispin as the second installment in Star Wars: The Han Solo Trilogy. It was later identified by name in Rebel Dawn, the third installment of the trilogy that was also written by Crispin and published in 1998.