Roblox checkpoint system script

-- Checkpoint system for an obby.
-- Put your checkpoint Parts in a Folder in the Workspace named "Checkpoints".
-- Name them 1, 2, 3 ... in the order players reach them.

local FOLDER_NAME = "Checkpoints"
local SPAWN_HEIGHT = 4        -- studs above the checkpoint to place the player

local Players = game:GetService("Players")

local folder = workspace:WaitForChild(FOLDER_NAME)

local function getStage(player)
	local leaderstats = player:FindFirstChild("leaderstats")
	if not leaderstats then
		leaderstats = Instance.new("Folder")
		leaderstats.Name = "leaderstats"
		leaderstats.Parent = player
	end

	local stage = leaderstats:FindFirstChild("Stage")
	if not stage then
		stage = Instance.new("IntValue")
		stage.Name = "Stage"
		stage.Value = 0
		stage.Parent = leaderstats
	end
	return stage
end

local function onPlayerAdded(player)
	local stage = getStage(player)

	player.CharacterAdded:Connect(function(character)
		if stage.Value == 0 then
			return -- no checkpoint reached yet; use the normal spawn
		end

		local checkpoint = folder:FindFirstChild(tostring(stage.Value))
		local root = character:WaitForChild("HumanoidRootPart", 5)
		if checkpoint and root then
			character:PivotTo(checkpoint.CFrame + Vector3.new(0, checkpoint.Size.Y / 2 + SPAWN_HEIGHT, 0))
		end
	end)
end

Players.PlayerAdded:Connect(onPlayerAdded)
for _, player in Players:GetPlayers() do
	task.spawn(onPlayerAdded, player)
end

-- Set up each checkpoint.
for _, checkpoint in folder:GetChildren() do
	local number = tonumber(checkpoint.Name)
	if number and checkpoint:IsA("BasePart") then
		checkpoint.Touched:Connect(function(hit)
			local player = Players:GetPlayerFromCharacter(hit.Parent)
			if not player then
				return
			end
			local stage = getStage(player)
			if number > stage.Value then
				stage.Value = number
			end
		end)
	end
end