A MONKEY GOD
Hanuman, also known as Pawan Putra, an Incarnation of Lord Shiva was born to the Anjana and Kesari. Anjana, his mother was an aspara and born on earth due to curse she was suffering. She worshipped Shiva to have him as her child. On getting her wish granted to have Hanuman, she released from the curse.
Lord Hanuman was believed to have combined powers of all the god and goddess. Once in his childhood his captured ‘Sun’ in his mouth, which created the blackness in the world. Due to this instance all the god prayed to Hanuman to release the sun and save the world. When hanuman released sun from his mouth, each god present in the universe gave him their power as a gift. But, he can only use this power whenever he will be reminded of it because he was very mischievous at his childhood.
Lord Shiva took birth in the avatar of hanuman to help lord Rama in his quest to find sita and fight Ravana, the demon god. Ravana, inherited many Sidhiyas from Lord Shiva by Sadhanas and Jap, the recitation of Shiva mantras and prayers. His is also the dearest devotee of Lord Shiva and was greatest troublemaker to gods. As ravana possess powers of Lord shiva and no one else in the universe can combat him except Shiva. Due to this fact lord shiva has to take birth in the Avatar of Lord Hanuman. While on the other hand, Lord Rama, an incarnation of Lord Vishnu took birth to Kill the ravana from his own hand because Ravana wished to be killed by the hands of Almighty god, Shiva or Vishnu.