Who was the son of Bhima and the demoness Hidimba?

Ghatotkacha was the son of Bhima and the rakshasi Hidimbi.

Bhima met Hidimbi while the Pandavas were hiding in a forest after escaping the burning House of Lac. Her brother Hidimba wanted to kill and eat the travelers, but Hidimbi warned them and fell in love with Bhima. Bhima slew Hidimba, and he and Hidimbi later had a son, Ghatotkacha.

Ghatotkacha inherited extraordinary strength and supernatural abilities associated with his rakshasa heritage. His name is commonly explained through the Sanskrit words for “pot” and “head,” referring to his bald, rounded head. He grew up mainly under Hidimbi’s care but remained an important ally of the Pandavas.

During the Kurukshetra War, Ghatotkacha commanded a major Pandava force and fought especially powerfully at night. His attacks became so devastating that Karna used the divine Vasavi Shakti weapon against him. Ghatotkacha died, but his death forced Karna to expend the weapon intended for Arjuna.