When Lord Hanuman Indulged in a very struggle with Ahiravana, he discovered that it was not possible to kill Ahiravana in the battle, and there needs to be some secret about his death. जो सुमिरै हनुमत बलबीरा ॥३६॥ जय जय जय हनुमान गोसाईं । Afterward, Hanuman retires on the Himalayas https://www.youtube.com/watch?v=ufkmD95y7fE&t=1s