Watch_Dogs Legion UNITED is a custom multiplayer modding platform.
Our initial Early Access release contains a Deathmatch gamemode, with the intention to stress–test weapon and on–foot synchronization, as well as general stability and performance testing. NOMAD Group is hosting these Deathmatch servers, in which you will be able to play a free–for–all mode with up to 32 players.
Our most recent Q&A can be found here: Dev Blog #16
Install instructions and download are available here