--=====================================================
-- SETTINGS (easy to edit)
--=====================================================
local KILL_RADIUS = 100            -- studs
local CHECK_INTERVAL = 0.2         -- seconds between scans
local UNLOAD_KEY = Enum.KeyCode.M  -- key to unload script
local TAG_NAME = "NPC_KILLER"      -- internal tag name

--=====================================================
-- SERVICES
--=====================================================
local Players = game:GetService("Players")
local RunService = game:GetService("RunService")
local UIS = game:GetService("UserInputService")

local player = Players.LocalPlayer
local character = player.Character or player.CharacterAdded:Wait()

--=====================================================
-- REMOVE OLD COPIES
--=====================================================
if _G[TAG_NAME] then
    _G[TAG_NAME].Unload()
end

local runtime = {}
_G[TAG_NAME] = runtime

runtime.alive = true
runtime.connections = {}

print("[NPC Killer] Loaded")

--=====================================================
-- FUNCTION: KILL NPCs
--=====================================================
local function killNPCs()
    local root = character:FindFirstChild("HumanoidRootPart")
    if not root then return end
    
    for _, model in pairs(workspace:GetDescendants()) do
        if model:IsA("Model") and model ~= character then
            
            local hum = model:FindFirstChildOfClass("Humanoid")
            local hrp = model:FindFirstChild("HumanoidRootPart")
            
            if hum and hrp and hum.Health > 0 then
                local dist = (hrp.Position - root.Position).Magnitude
                
                if dist <= KILL_RADIUS then
                    hum.Health = 0
                end
            end
            
        end
    end
end

--=====================================================
-- LOOP
--=====================================================
task.spawn(function()
    while runtime.alive do
        killNPCs()
        task.wait(CHECK_INTERVAL)
    end
end)

--=====================================================
-- UNLOAD FUNCTION
--=====================================================
function runtime.Unload()
    runtime.alive = false
    
    for _,c in pairs(runtime.connections) do
        pcall(function()
            c:Disconnect()
        end)
    end
    
    _G[TAG_NAME] = nil
    
    print("[NPC Killer] Unloaded")
end

--=====================================================
-- KEYBIND
--=====================================================
table.insert(runtime.connections,
    UIS.InputBegan:Connect(function(input, gp)
        if gp then return end
        
        if input.KeyCode == UNLOAD_KEY then
            runtime.Unload()
        end
    end)
)