Roblox npc follows player script

-- NPC that follows the nearest player using PathfindingService.
-- The model needs a Humanoid and a HumanoidRootPart.

local DETECT_RANGE = 80       -- studs; ignores players further away
local STOP_DISTANCE = 5       -- studs; stops when this close
local UPDATE_TIME = 0.4       -- seconds between path updates

local Players = game:GetService("Players")
local PathfindingService = game:GetService("PathfindingService")

local npc = script.Parent
local humanoid = npc:WaitForChild("Humanoid")
local root = npc:WaitForChild("HumanoidRootPart")

-- Let the server move the NPC smoothly (no stutter from a nearby player owning it).
pcall(function()
	root:SetNetworkOwner(nil)
end)

local function findNearestTarget()
	local nearestRoot = nil
	local nearestDistance = DETECT_RANGE

	for _, player in Players:GetPlayers() do
		local character = player.Character
		local targetHumanoid = character and character:FindFirstChildOfClass("Humanoid")
		local targetRoot = character and character:FindFirstChild("HumanoidRootPart")
		if targetHumanoid and targetRoot and targetHumanoid.Health > 0 then
			local distance = (targetRoot.Position - root.Position).Magnitude
			if distance < nearestDistance then
				nearestDistance = distance
				nearestRoot = targetRoot
			end
		end
	end

	return nearestRoot, nearestDistance
end

while humanoid.Health > 0 do
	local targetRoot, distance = findNearestTarget()

	if targetRoot and distance > STOP_DISTANCE then
		local path = PathfindingService:CreatePath({
			AgentRadius = 2,
			AgentHeight = 5,
			AgentCanJump = true,
		})

		local ok = pcall(function()
			path:ComputeAsync(root.Position, targetRoot.Position)
		end)

		if ok and path.Status == Enum.PathStatus.Success then
			local waypoints = path:GetWaypoints()
			local nextWaypoint = waypoints[2] -- waypoint 1 is where the NPC already stands
			if nextWaypoint then
				if nextWaypoint.Action == Enum.PathWaypointAction.Jump then
					humanoid.Jump = true
				end
				humanoid:MoveTo(nextWaypoint.Position)
			end
		else
			-- No path found: walk straight at the player.
			humanoid:MoveTo(targetRoot.Position)
		end
	end

	task.wait(UPDATE_TIME)
end