According to Shaivites, Shiva himself descended as Hanuman to destroy Ravana, an errant Shiva-bhakta. According to them, Ravana had offered his ten heads to Shiva and obtained boons that made him very powerful. But as Rudra, Shiva has eleven forms. Ravana’s offering of ten heads satisfied the ten forms of Rudra. The eleventh unhappy Rudra took birth as Hanuman to kill Ravana. Hence Hanuman is also Raudreya.
