“You will therefore be taken to the Dune Sea and cast into the Pit of Carkoon, the nesting place of the all-powerful Sarlacc. In his belly, you will find a new definition of pain and suffering, as you are slowly digested over a thousand years.”
―C-3PO describing the Sarlaac
The Sarlacc is a semi-sentient plant-like omnivorous creature that lived on Tatooine and other planets in the galaxy. It is located at the Pit of Carkoon in the Dune Sea. It catches its prey like an antlion whenever any lifeform slides down into the pit, such as when it swallowed Boba Fett. A Sarlacc's only predator was the Greater Krayt Dragon.
The Sarlacc first appears in this film. After Luke Skywalker kills Jabba the Hutt's pet rancor and Han Solo and Chewbacca are imprisoned, Jabba orders for Luke, Han, and Chewbacca to be executed by being fed to the Sarlacc, a colossal creature that lives in the Great Pit of Carkoon, where they are to be digested over the course of a thousand years. Lando Calrissian, Leia Organa, C-3PO, and R2-D2 stage a rescue that results in the deaths of Jabba and most of his posse, many of whom are eaten by the Sarlacc. After destroying Jabba's sail barge, the group flees the site of the battle to regroup with the Rebellion.
The Sarlacc makes a brief cameo in the opening song of "Phineas and Ferb: Star Wars", where Phineas and Ferb where sand-boarding down a hill and jumped over the Sarlacc. It was also mentioned that Phineas and Ferb brushed the Sarlacc's teeth. Lastly, the Phineas and Ferb Star Wars song "I'm Feelin' So Low" has a line mentioning the Sarlacc pit.
The Sarlacc makes an appearance in both the Twilight of the Republic and Rise Against the Empire play sets and as a Toy Box set piece.
In the original release, the Sarlacc was just a hole with teeth. In the special edition tentacles and a large squawking beak were added. It was because George Lucas felt that it didn't look alive enough.