http://www.pcgamer.com/overwatch-deathmatch-modes-are-now-open-to-everyone/

Earlier this month, Blizzard rolled out new "Free-For-All" and "Team Deathmatch" game modes on the Overwatch PTR, where they could be put through their paces before being released to the world at large. Today the studio announced that those paces have been put, and that both modes are now open to everyone on the Overwatch Arcade. 

Free-For-All—known colloquially to industry insiders as "FFA"—is an eight-way race to 20 kills: Whoever gets there first wins the match. Team Deathmatch is slightly more organized, as two teams of six battle to be the first to 30 kills, a process complicated somewhat by the fact that Mercy resurrections will reduce kill counts. Blizzard said that "several" maps are being modified for the new modes, and a new one called Château Guillard is being released specifically for FFA.