OP Kill All Zombie Open Source

local GetService = game.GetService

--

local Workspace = GetService(game, "Workspace")
local Players = GetService(game, "Players")

--
local NPCs = Workspace.Game.Current.Spawned.NPCs.enemies
local LocalPlayer = Players.LocalPlayer

while task.wait(0.1) do
    -- 
    local Character = LocalPlayer.Character
    if not Character then continue end

    local Tool = Character:FindFirstChildOfClass("Tool")
    if not Tool then continue end
	
    local ServerEvents = Tool.ServerEvents
    local Fired = ServerEvents.Fired
    local RegisterHit = ServerEvents.RegisterHit
    --
    if NPCs then
        for _, NPC in ipairs(NPCs:GetChildren()) do
            if not NPC:IsA("Model") then continue end

            local Head = NPC:FindFirstChild("Head")
            if not Head then continue end

            local Humanoid = NPC:FindFirstChildOfClass("Humanoid")
            if not Humanoid or Humanoid.Health <= 0 then continue end

            Fired:FireServer()
            RegisterHit:FireServer(
                {{
                    amount = 9e9,
                    target = NPC,
                    is_friendly = false,
                    part = Head,
                    cast_results = nil
                }},
                {{
                    normal = Vector3.new(0,0,0),
                    part = Head,
                    distance = 0,
                    material = Enum.Material.Plastic,
                    pos = Head.Position
                }}
            )
        end
    end
end