During the reign of Madakari Nayaka, the city of Chitradurga was besieged by the troops of Hyder Ali. A chance sighting of a woman entering the Chitradurga fort through a crack hole in the rocks led to a clever plan by Hyder Ali to send his soldiers through the crack hole. The defense guard on duty of the port near that crack hole had just gone home as usual asking his wife to guard till he is back from his lunch. The wife of that guard, Obavva while in her temporary seat, noticed the soldiers emerging out of this crack. Obavva was not perturbed. As she was carrying with her, the Onake (a wooden long club meant for pounding paddy grains) she killed and quietly moved the dead, so that hundreds of them entered and fell, without raising any suspicion. The guard, Obavva's husband, upon his return from his lunch was shocked to see Obavva standing with a blood stained Onake and hundreds of dead bodies of the enemy fleet around her. The passage still remains as a historical witness for the story. Though her sincere brave attempt saved the fort this time, Madakari could not resist the attack of 1799 by Hyder Ali. The fort of Chitradurga was lost for Hyder Ali once for all. She killed 138 soldiers single handedly.