Gamers who are thinking of running multiplayer mods of Dead Island on their Steam account don't have to worry about Valve Anti-Cheat System (VAC) bans.
This was spotted by a "can modding dead island get me vac banned?" The simple answer from Steam Support was "No."from Steam Support responding to a user named mund0x who
So, go ahead and mod Dead Island to your hearts content. Just don't pirate it, or go onto Steam with a hacked version and ruin everyone's day in multiplayer.