local plr = game.Players.LocalPlayer
local char = plr.Character or plr.CharacterAdded:Wait()
local hum = char:WaitForChild("Humanoid")
local playerGui = plr:WaitForChild("PlayerGui")

-- Session memory
local unlockFlag = playerGui:FindFirstChild("MonsterMashUnlocked")
if not unlockFlag then
	unlockFlag = Instance.new("BoolValue")
	unlockFlag.Name = "MonsterMashUnlocked"
	unlockFlag.Value = false
	unlockFlag.Parent = playerGui
end

-- GUI
local gui = Instance.new("ScreenGui", playerGui)
gui.Name = "MonsterMashGUI"

local frame = Instance.new("Frame", gui)
frame.Size = UDim2.new(0, 340, 0, 200)
frame.Position = UDim2.new(0.5, -170, 0.5, -100)
frame.BackgroundColor3 = Color3.fromRGB(25, 25, 25)
frame.Active = true
frame.Draggable = true

local title = Instance.new("TextLabel", frame)
title.Size = UDim2.new(1, 0, 0, 40)
title.Text = "🎃 Monster Mash Dance 🎃"
title.BackgroundTransparency = 1
title.TextColor3 = Color3.fromRGB(255, 170, 0)
title.Font = Enum.Font.GothamBold
title.TextSize = 24

local password = Instance.new("TextBox", frame)
password.Size = UDim2.new(1, -40, 0, 35)
password.Position = UDim2.new(0, 20, 0, 50)
password.PlaceholderText = "Enter Password"
password.Text = ""
password.Font = Enum.Font.Gotham
password.TextSize = 20
password.BackgroundColor3 = Color3.fromRGB(40, 40, 40)
password.TextColor3 = Color3.new(1, 1, 1)
password.Visible = not unlockFlag.Value

local startBtn = Instance.new("TextButton", frame)
startBtn.Size = UDim2.new(0.4, 0, 0, 40)
startBtn.Position = UDim2.new(0.05, 0, 0, 100)
startBtn.Text = "Start"
startBtn.BackgroundColor3 = Color3.fromRGB(0, 170, 0)
startBtn.TextColor3 = Color3.new(1, 1, 1)
startBtn.Font = Enum.Font.GothamBold
startBtn.TextSize = 20
startBtn.Visible = unlockFlag.Value

local stopBtn = Instance.new("TextButton", frame)
stopBtn.Size = UDim2.new(0.4, 0, 0, 40)
stopBtn.Position = UDim2.new(0.55, 0, 0, 100)
stopBtn.Text = "Stop"
stopBtn.BackgroundColor3 = Color3.fromRGB(170, 0, 0)
stopBtn.TextColor3 = Color3.new(1, 1, 1)
stopBtn.Font = Enum.Font.GothamBold
stopBtn.TextSize = 20
stopBtn.Visible = unlockFlag.Value

-- Animation setup
local anim = Instance.new("Animation")
anim.AnimationId = "rbxassetid://35654637" -- R6 Monster Mash dance
local animTrack

-- Music
local function playMusic()
	local existing = workspace:FindFirstChild("MonsterMashSound")
	if existing then return end
	local sound = Instance.new("Sound")
	sound.Name = "MonsterMashSound"
	sound.SoundId = "rbxassetid://35930009" -- Monster Mash music
	sound.Volume = 1
	sound.Looped = true
	sound.Parent = workspace
	sound:Play()
end

local function stopMusic()
	local sound = workspace:FindFirstChild("MonsterMashSound")
	if sound then
		sound:Stop()
		sound:Destroy()
	end
end

-- Password logic
password.FocusLost:Connect(function(enterPressed)
	if enterPressed then
		if password.Text:lower() == "monsterzrz" then
			unlockFlag.Value = true
			password.Visible = false
			startBtn.Visible = true
			stopBtn.Visible = true
		else
			password.Text = ""
			password.PlaceholderText = "Wrong, try again"
		end
	end
end)

-- Button logic
startBtn.MouseButton1Click:Connect(function()
	if animTrack then animTrack:Stop() end
	animTrack = hum:LoadAnimation(anim)
	animTrack:Play()
	playMusic()
end)

stopBtn.MouseButton1Click:Connect(function()
	if animTrack then animTrack:Stop() end
	stopMusic()
end)

-- Handle respawn
plr.CharacterAdded:Connect(function(newChar)
	char = newChar
	hum = char:WaitForChild("Humanoid")
end)