Wikipedia
In Hinduism, KhatuShyam is a name and manifestation of Barbarik, son of Ghatotkach grandson of Bhima. This manifestation is especially popular in the Indian state of Rajasthan and Haryana. The original Sanskrit name Barbarīka is often replaced in Rajasthan by the Hindi version, Barbarīk, often written as Barbareek.
Barbarika had obtained a boon from Krishna to the effect that he would be known by Krishna's own name (Shyam) in the Kaliyuga era (presently ongoing) and worshiped. Krishna had declared that Barbarika's devotees would be blessed just by pronouncing his name from the bottom of their hearts. Their wishes would be granted and troubles removed if they worship Shyamji (Barbarika) with a true piety.