https://www.pcgamer.com/the-underhollow-dota-2s-battle-royale-with-cheese-is-now-live/

The Underhollow, the Dota 2 battle royale with cheese mode that was announced in May, is now live. The new mode is available exclusively to owners of the 2018 International Battle Pass, a multi-level offering for Dota fans that also includes new modes, sprays, a Cavern Crawl, and other rewards. 

The Underhollow pits eight teams of three players each against one other in a great quest for Roshefort, the rarest of all cheese located in the caverns beneath Roshan's lair. But the other cheese-chasing teams are just the start of your problems: Roshan himself is also that sharp, savory flavor, and his rambunctious roaming is causing the tunnels to collapse, slowly constricting the playing area.