DARPA designed the Subterranean Challenge motivated primarily by warfighter needs, as well as those of the first responder communities. The challenge is inspired by the need to conduct search and rescue missions in a variety of underground environments, whether in response to an incident in a highly populated area, a natural disaster, or for mine rescue. A team of various robots is required to enter underground environment, map it and locate objects of interest with very little or no human supervision. The talk will detail the approach of the best DARPA-non-funded team which has performed better than most of the DARPA funded teams.