I don't know about invisible players, but I did tinker the scripts file of all firearms to one shot regular zombies regardless of headshots. For melee weapons I've yet to figure it out, but I assume that you have to find the .xml or .bmd file that's controlling: - Blunt Knockdown Chance factor for Blunt Weapons - Decapitation Chance factor for Edged Weapons - Mighty Blow Chance factor for Heavy Weapons here is the mod link: One Hit Kill with All Firearms at State of Decay Nexus - Mods and community (nexusmods.com)