Killing of Viradha
On their way to forest Ramachandra and Laxman killed many vicious demons. One day, Viradha the powerful demon caught them unawares and started chasing. Viradha had a special power in that he could not be killed with any weapon. Knowing this fact, Rama grounded and stood on him. Laxman dug a moat, and Viradha was buried live.
Chitra Ramayana