The Sher Kar cave was the lair of a group of Sher Kar beneath Tulrus Island on Mustafar. To reach the cave, one had to travel across a long valley on the Tulrus Island full of dangerous tulrus. Mustafarian legends claimed that no one who entered a Sher Kar's lair returned alive.
In this cave dwelled a giant Sher Kar along with smaller karklings, praetorians and a symbiot. Lava geodes could be found scattered throughout the cave. Lava pools spread intense heat and hot gases erupted in several locations in the cave. The obnoxious fumes inside the cave forbde entry to all who did not have an omniglobular syringe.
Members of a biological survey project once visited Mustafar on an expedition and found the cave while investigating the tulrus. The researchers were detected and attacked but were ablo to get away. During the Galactic Civil War, a group of spacers ventured into the cave and managed to kill the Sher Kars inside.