Well if you ever dreamed of Overwatch Deathmatch free for all, your dreams are coming true next patch to the PTR. In the arcade your will now be able to pick Deathmatch free for all where your play against 7 other people trying to be the first to get 20 kills. Team Deathmatch is two teams of 6 facing off to be the first team to reach 20 kills total. There are some very interesting aspects to both modes, new maps and interesting character mechanics like mercy rez gaining kills back for your team...stuff like that.
Here is a video of Jeff Kaplan gong over more features of the upcoming Deathmatch mode in Overwatch. Enjoy.