"NPC that stalks and kills, avanced and complete script"

-- creating an NPC that stalks and kills players 
local pfs = game:GetService("PathfindingService")
local npc = game.Workspace.NPC
local aggroRange = 50
local attackRange = 5
local attackCooldown = 2
local attacking = false

local function findNearestPlayer()
    local nearestPlayer = nil
    local nearestDistance = math.huge
    for _, player in ipairs(game.Players:GetPlayers()) do
        if player.Character and player.Character:FindFirstChild("HumanoidRootPart") then
            local distance = (npc.HumanoidRootPart.Position - player.Character.HumanoidRootPart.Position).Magnitude
            if distance < nearestDistance then
                nearestDistance = distance
                nearestPlayer = player
            end
        end
    end
    return nearestPlayer, nearestDistance
end

local function moveToTarget(target)
    local path = pfs:CreatePath()
    path:ComputeAsync(npc.HumanoidRootPart.Position, target.Position)
    for _, waypoint in pairs(path:GetWaypoints()) do
        npc.Humanoid:MoveTo(waypoint.Position)
        npc.Humanoid.MoveToFinished:Wait()
    end
end

local function attack(target)
    if not attacking then
        attacking = true
        npc.Humanoid:MoveTo(target.HumanoidRootPart.Position)
        wait(attackCooldown)
        if (npc.HumanoidRootPart.Position - target.HumanoidRootPart.Position).Magnitude <= attackRange then
            target.Humanoid:TakeDamage(npc.Humanoid.Health / 2)
        end
        attacking = false
    end
end

while true do
    local nearestPlayer, nearestDistance = findNearestPlayer()
    if nearestPlayer and nearestDistance <= aggroRange then
        if nearestDistance <= attackRange then
            attack(nearestPlayer.Character)
        else
            moveToTarget(nearestPlayer.Character.HumanoidRootPart)
        end
    else
        wait(1)
    end
end