--========================================================--
-- A-train ability
-- R6 + R15
========================================================--

local Players = game:GetService("Players")
local RunService = game:GetService("RunService")
local Debris = game:GetService("Debris")
local TweenService = game:GetService("TweenService")

local Player = Players.LocalPlayer

--========================================================--
-- SETTINGS
--========================================================--

local TOOL_NAME = "A-train run"

local NORMAL_SPEED = 16
local SUPER_SPEED = 110

local ABILITY_TIME = 5
local COOLDOWN = 3

local HIT_RADIUS = 4

local LIGHTNING_INTERVAL = 0.045
local LIGHTNING_LENGTH = 18
local LIGHTNING_POINTS = 12
local LIGHTNING_LIFETIME = 0.16

local SPEED_SOUND_ID = "rbxassetid://18250758551"
local EXPLOSION_SOUND_ID = "rbxassetid://138186576"

local STREAK_REQUIRED = 2
local STREAK_TIMEOUT = 5

--========================================================--
-- CHARACTER
--========================================================--

local Character
local Humanoid
local Root

local function SetupCharacter(Char)
	Character = Char
	Humanoid = Char:WaitForChild("Humanoid")
	Root = Char:WaitForChild("HumanoidRootPart")
end

if Player.Character then
	SetupCharacter(Player.Character)
end

Player.CharacterAdded:Connect(function(Char)
	SetupCharacter(Char)
end)

--========================================================--
-- REMOVE OLD TOOL
--========================================================--

local function RemoveOldTools()

	local Backpack = Player:WaitForChild("Backpack")

	local OldTool = Backpack:FindFirstChild(TOOL_NAME)

	if OldTool then
		OldTool:Destroy()
	end

	if Character then

		local EquippedTool =
			Character:FindFirstChild(TOOL_NAME)

		if EquippedTool then
			EquippedTool:Destroy()
		end
	end
end

RemoveOldTools()

--========================================================--
-- CREATE TOOL
--========================================================--

local Tool = Instance.new("Tool")

Tool.Name = TOOL_NAME
Tool.RequiresHandle = false
Tool.CanBeDropped = false
Tool.ToolTip = "Activate super speed"

Tool.Parent = Player:WaitForChild("Backpack")

--========================================================--
-- VARIABLES
--========================================================--

local Active = false
local OnCooldown = false

local Streak = 0
local AlreadyHit = {}

local LightningConnection
local HitConnection
local ShakeConnection

local SpeedSound

--========================================================--
-- GUI
--========================================================--

local PlayerGui =
	Player:WaitForChild("PlayerGui")

local OldGui =
	PlayerGui:FindFirstChild("SpeedToolStreakGUI")

if OldGui then
	OldGui:Destroy()
end

local Gui =
	Instance.new("ScreenGui")

Gui.Name =
	"SpeedToolStreakGUI"

Gui.ResetOnSpawn = false
Gui.IgnoreGuiInset = true
Gui.DisplayOrder = 999999
Gui.Parent = PlayerGui

--========================================================--
-- STREAK BUTTON
--========================================================--

local StreakButton =
	Instance.new("TextButton")

StreakButton.Name =
	"StreakButton"

StreakButton.Size =
	UDim2.new(0, 130, 0, 55)

StreakButton.Position =
	UDim2.new(0, 20, 1, -135)

StreakButton.BackgroundColor3 =
	Color3.fromRGB(25, 25, 35)

StreakButton.Text =
	"STREAK: 0"

StreakButton.TextColor3 =
	Color3.fromRGB(255, 255, 255)

StreakButton.TextScaled = true
StreakButton.Font =
	Enum.Font.GothamBold

StreakButton.Parent = Gui

local StreakCorner =
	Instance.new("UICorner")

StreakCorner.CornerRadius =
	UDim.new(0, 16)

StreakCorner.Parent =
	StreakButton

local StreakStroke =
	Instance.new("UIStroke")

StreakStroke.Thickness = 2

StreakStroke.Color =
	Color3.fromRGB(0, 170, 255)

StreakStroke.Parent =
	StreakButton

--========================================================--
-- STREAK TEXT
--========================================================--

local StreakText =
	Instance.new("TextLabel")

StreakText.Name =
	"StreakText"

StreakText.AnchorPoint =
	Vector2.new(0.5, 0)

StreakText.Position =
	UDim2.new(0.5, 0, 0, 45)

StreakText.Size =
	UDim2.new(0, 500, 0, 90)

StreakText.BackgroundTransparency = 1

StreakText.Text = ""

StreakText.TextColor3 =
	Color3.fromRGB(0, 200, 255)

StreakText.TextStrokeColor3 =
	Color3.fromRGB(0, 20, 60)

StreakText.TextStrokeTransparency = 0

StreakText.TextScaled = true

StreakText.Font =
	Enum.Font.GothamBlack

StreakText.Visible = false

StreakText.Parent = Gui

--========================================================--
-- STREAK SHAKE
--========================================================--

local function StopStreakShake()

	if ShakeConnection then

		ShakeConnection:Disconnect()

		ShakeConnection = nil
	end
end

local function StartStreakShake()

	StopStreakShake()

	ShakeConnection =
		RunService.RenderStepped:Connect(
			function()

				if not StreakText.Visible then
					return
				end

				local X =
					math.random(-6, 6)

				local Y =
					math.random(-4, 4)

				StreakText.Position =
					UDim2.new(
						0.5,
						X,
						0,
						45 + Y
					)
			end
		)
end

--========================================================--
-- SHOW STREAK
--========================================================--

local function ShowStreak()

	if Streak < STREAK_REQUIRED then
		return
	end

	StreakText.Visible = true

	StreakText.Text =
		"STREAK x" ..
		tostring(Streak)

	StreakText.TextTransparency = 0
	StreakText.TextStrokeTransparency = 0

	StartStreakShake()

	StreakText.Size =
		UDim2.new(0, 430, 0, 75)

	local Grow =
		TweenService:Create(
			StreakText,

			TweenInfo.new(
				0.15,
				Enum.EasingStyle.Back,
				Enum.EasingDirection.Out
			),

			{
				Size =
					UDim2.new(
						0,
						500,
						0,
						90
					)
			}
		)

	Grow:Play()
end

--========================================================--
-- END STREAK
--========================================================--

local function EndStreak()

	Streak = 0

	StreakButton.Text =
		"STREAK: 0"

	StopStreakShake()

	local Fade =
		TweenService:Create(
			StreakText,

			TweenInfo.new(0.25),

			{
				TextTransparency = 1,
				TextStrokeTransparency = 1
			}
		)

	Fade:Play()

	Fade.Completed:Connect(
		function()

			StreakText.Visible = false

			StreakText.Text = ""

			StreakText.TextTransparency = 0

			StreakText.TextStrokeTransparency = 0
		end
	)
end

--========================================================--
-- NPC CHECK
--========================================================--

local function IsNPC(Model)

	if not Model
		or not Model:IsA("Model") then

		return false
	end

	local NPC_Humanoid =
		Model:FindFirstChildOfClass(
			"Humanoid"
		)

	if not NPC_Humanoid then
		return false
	end

	-- NEVER HIT PLAYERS
	if Players:GetPlayerFromCharacter(Model) then
		return false
	end

	return NPC_Humanoid.Health > 0
end

--========================================================--
-- EXPLOSION
--========================================================--

local function ExplosionEffect(Position)

	local Holder =
		Instance.new("Part")

	Holder.Anchored = true
	Holder.CanCollide = false
	Holder.CanTouch = false
	Holder.CanQuery = false
	Holder.Transparency = 1

	Holder.Size =
		Vector3.new(1, 1, 1)

	Holder.Position = Position
	Holder.Parent = workspace

	-- Sphere
	local Sphere =
		Instance.new("Part")

	Sphere.Shape =
		Enum.PartType.Ball

	Sphere.Anchored = true

	Sphere.CanCollide = false
	Sphere.CanTouch = false
	Sphere.CanQuery = false

	Sphere.Material =
		Enum.Material.Neon

	Sphere.Color =
		Color3.fromRGB(
			0,
			170,
			255
		)

	Sphere.Transparency = 0.15

	Sphere.Size =
		Vector3.new(1, 1, 1)

	Sphere.Position = Position

	Sphere.Parent = Holder

	local SphereTween =
		TweenService:Create(
			Sphere,

			TweenInfo.new(
				0.25,
				Enum.EasingStyle.Quad,
				Enum.EasingDirection.Out
			),

			{
				Size =
					Vector3.new(
						9,
						9,
						9
					),

				Transparency = 1
			}
		)

	SphereTween:Play()

	-- Ring
	local Ring =
		Instance.new("Part")

	Ring.Shape =
		Enum.PartType.Cylinder

	Ring.Anchored = true

	Ring.CanCollide = false
	Ring.CanTouch = false
	Ring.CanQuery = false

	Ring.Material =
		Enum.Material.Neon

	Ring.Color =
		Color3.fromRGB(
			0,
			100,
			255
		)

	Ring.Transparency = 0.1

	Ring.Size =
		Vector3.new(
			0.15,
			2,
			2
		)

	Ring.CFrame =
		CFrame.new(Position) *
		CFrame.Angles(
			0,
			0,
			math.rad(90)
		)

	Ring.Parent = Holder

	local RingTween =
		TweenService:Create(
			Ring,

			TweenInfo.new(
				0.3,
				Enum.EasingStyle.Quad,
				Enum.EasingDirection.Out
			),

			{
				Size =
					Vector3.new(
						0.15,
						8,
						8
					),

				Transparency = 1
			}
		)

	RingTween:Play()

	-- Sound
	local Sound =
		Instance.new("Sound")

	Sound.SoundId =
		EXPLOSION_SOUND_ID

	Sound.Volume = 1

	Sound.Parent =
		Holder

	Sound:Play()

	Debris:AddItem(
		Holder,
		0.5
	)
end

--========================================================--
-- SPEED HIT SOUND
--========================================================--

local function PlayHitSound()

	if not Root
		or not Root.Parent then

		return
	end

	local Sound =
		Instance.new("Sound")

	Sound.Name =
		"SpeedHitSound"

	Sound.SoundId =
		SPEED_SOUND_ID

	Sound.Volume = 0.8
	Sound.PlaybackSpeed = 1
	Sound.Looped = false

	Sound.Parent = Root

	Sound:Play()

	Debris:AddItem(
		Sound,
		5
	)
end

--========================================================--
-- REGISTER KILL
--========================================================--

local function RegisterKill(NPC)

	if not NPC then
		return
	end

	if AlreadyHit[NPC] then
		return
	end

	AlreadyHit[NPC] = true

	Streak += 1

	StreakButton.Text =
		"STREAK: " ..
		tostring(Streak)

	if Streak >= STREAK_REQUIRED then
		ShowStreak()
	end

	local CurrentStreak =
		Streak

	task.delay(
		STREAK_TIMEOUT,

		function()

			if Streak == CurrentStreak then
				EndStreak()
			end
		end
	)

	--====================================================--
	-- HIT NPC = RESET COOLDOWN
	--====================================================--

	OnCooldown = false

	--====================================================--
	-- HIT NPC = PLAY SOUND AGAIN
	--====================================================--

	PlayHitSound()
end

--========================================================--
-- LIGHTNING
--========================================================--

local function GenerateLightningLine()

	if not Root
		or not Root.Parent then

		return
	end

	local Folder =
		Instance.new("Folder")

	Folder.Name =
		"LightningLine"

	Folder.Parent =
		workspace

	local Anchor =
		Instance.new("Part")

	Anchor.Name =
		"LightningAnchor"

	Anchor.Anchored = true

	Anchor.CanCollide = false
	Anchor.CanTouch = false
	Anchor.CanQuery = false

	Anchor.Transparency = 1

	Anchor.Size =
		Vector3.new(
			0.1,
			0.1,
			0.1
		)

	Anchor.CFrame =
		Root.CFrame

	Anchor.Parent =
		Folder

	local Attachments = {}

	for i = 1, LIGHTNING_POINTS do

		local Attachment =
			Instance.new("Attachment")

		local Alpha =
			(i - 1) /
			(LIGHTNING_POINTS - 1)

		local Z =
			Alpha *
			LIGHTNING_LENGTH

		Attachment.Position =
			Vector3.new(
				math.random(-20, 20) / 10,
				math.random(-15, 15) / 10,
				Z
			)

		Attachment.Parent =
			Anchor

		table.insert(
			Attachments,
			Attachment
		)
	end

	for i = 1, #Attachments - 1 do

		local Beam =
			Instance.new("Beam")

		Beam.Attachment0 =
			Attachments[i]

		Beam.Attachment1 =
			Attachments[i + 1]

		Beam.FaceCamera = true

		Beam.Width0 = 0.14
		Beam.Width1 = 0.04

		Beam.LightEmission = 1
		Beam.LightInfluence = 0

		Beam.Color =
			ColorSequence.new(
				Color3.fromRGB(
					0,
					120,
					255
				),

				Color3.fromRGB(
					0,
					220,
					255
				)
			)

		Beam.Transparency =
			NumberSequence.new({
				NumberSequenceKeypoint.new(
					0,
					0
				),

				NumberSequenceKeypoint.new(
					0.8,
					0.1
				),

				NumberSequenceKeypoint.new(
					1,
					1
				)
			})

		Beam.Parent =
			Anchor
	end

	local Glow =
		Instance.new("PointLight")

	Glow.Color =
		Color3.fromRGB(
			0,
			150,
			255
		)

	Glow.Brightness = 2
	Glow.Range = 7

	Glow.Parent =
		Anchor

	Debris:AddItem(
		Folder,
		LIGHTNING_LIFETIME
	)
end

--========================================================--
-- START LIGHTNING
--========================================================--

local function StartLightning()

	if LightningConnection then
		LightningConnection:Disconnect()
	end

	local Last = 0

	LightningConnection =
		RunService.RenderStepped:Connect(
			function()

				if not Active then
					return
				end

				if not Root
					or not Root.Parent then
					return
				end

				local Now =
					os.clock()

				if Now - Last
					>= LIGHTNING_INTERVAL then

					Last = Now

					GenerateLightningLine()
				end
			end
		)
end

--========================================================--
-- STOP LIGHTNING
--========================================================--

local function StopLightning()

	if LightningConnection then

		LightningConnection:Disconnect()

		LightningConnection = nil
	end
end

--========================================================--
-- NPC HIT DETECTION
--========================================================--

local function StartHitDetection()

	if HitConnection then
		HitConnection:Disconnect()
	end

	HitConnection =
		RunService.Heartbeat:Connect(
			function()

				if not Active then
					return
				end

				if not Root
					or not Root.Parent then
					return
				end

				local Params =
					OverlapParams.new()

				Params.FilterType =
					Enum.RaycastFilterType.Exclude

				Params.FilterDescendantsInstances =
					{Character}

				local Parts =
					workspace:GetPartBoundsInRadius(
						Root.Position,
						HIT_RADIUS,
						Params
					)

				local Checked = {}

				for _, Part in ipairs(Parts) do

					local Model =
						Part:FindFirstAncestorOfClass(
							"Model"
						)

					if Model
						and not Checked[Model] then

						Checked[Model] = true

						if IsNPC(Model)
							and not AlreadyHit[Model] then

							local NPC_Humanoid =
								Model:FindFirstChildOfClass(
									"Humanoid"
								)

							if NPC_Humanoid
								and NPC_Humanoid.Health > 0 then

								-- Kill NPC
								NPC_Humanoid.Health = 0

								-- Explosion
								local NPC_Root =
									Model:FindFirstChild(
										"HumanoidRootPart"
									)
									or Model.PrimaryPart

								if NPC_Root then

									ExplosionEffect(
										NPC_Root.Position
									)
								end

								RegisterKill(Model)
							end
						end
					end
				end
			end
		)
end

--========================================================--
-- STOP HIT DETECTION
--========================================================--

local function StopHitDetection()

	if HitConnection then

		HitConnection:Disconnect()

		HitConnection = nil
	end
end

--========================================================--
-- CREATE MAIN SOUND
--========================================================--

local function CreateSpeedSound()

	if not Root then
		return
	end

	if SpeedSound then
		SpeedSound:Destroy()
	end

	SpeedSound =
		Instance.new("Sound")

	SpeedSound.Name =
		"SuperSpeedSound"

	SpeedSound.SoundId =
		SPEED_SOUND_ID

	SpeedSound.Volume = 0.8
	SpeedSound.PlaybackSpeed = 1
	SpeedSound.Looped = false

	SpeedSound.Parent =
		Root
end

--========================================================--
-- ACTIVATE SPEED
--========================================================--

local function ActivateSpeed()

	if Active then
		return
	end

	if OnCooldown then
		return
	end

	if not Character
		or not Humanoid
		or not Root then
		return
	end

	if Humanoid.Health <= 0 then
		return
	end

	Active = true
	OnCooldown = true

	AlreadyHit = {}

	Humanoid.WalkSpeed =
		SUPER_SPEED

	CreateSpeedSound()

	if SpeedSound then
		SpeedSound:Play()
	end

	StartLightning()
	StartHitDetection()

	task.delay(
		ABILITY_TIME,

		function()

			if not Active then
				return
			end

			Active = false

			if Humanoid
				and Humanoid.Parent then

				Humanoid.WalkSpeed =
					NORMAL_SPEED
			end

			StopLightning()
			StopHitDetection()

			if SpeedSound then

				SpeedSound:Stop()
				SpeedSound:Destroy()

				SpeedSound = nil
			end

			-- If an NPC was NOT hit,
			-- normal cooldown happens.
			if OnCooldown then

				task.delay(
					COOLDOWN,

					function()

						OnCooldown = false
					end
				)
			end
		end
	)
end

--========================================================--
-- TOOL ACTIVATED
--========================================================--

Tool.Activated:Connect(function()
	ActivateSpeed()
end)

--========================================================--
-- TOOL EQUIPPED
--========================================================--

Tool.Equipped:Connect(function()

	-- Make sure the GUI exists
	Gui.Enabled = true
end)

--========================================================--
-- TOOL UNEQUIPPED
--========================================================--

Tool.Unequipped:Connect(function()

	-- Keep streak UI visible
	-- even when the tool is unequipped.

	Gui.Enabled = true
end)

--========================================================--
-- STREAK BUTTON
--========================================================--

StreakButton.Activated:Connect(function()

	if Streak >= STREAK_REQUIRED then

		ShowStreak()

	else

		StreakButton.Text =
			"NEED 2 KILLS"

		task.delay(
			1,

			function()

				if StreakButton
					and Streak < STREAK_REQUIRED then

					StreakButton.Text =
						"STREAK: " ..
						tostring(Streak)
				end
			end
		)
	end
end)

--========================================================--
-- RESPAWN
--========================================================--

Player.CharacterAdded:Connect(
	function(NewCharacter)

		SetupCharacter(NewCharacter)

		Active = false
		OnCooldown = false

		Streak = 0
		AlreadyHit = {}

		StopLightning()
		StopHitDetection()
		StopStreakShake()

		if SpeedSound then

			SpeedSound:Destroy()
			SpeedSound = nil
		end

		StreakButton.Text =
			"STREAK: 0"

		StreakText.Visible = false
		StreakText.Text = ""

		-- Recreate tool if Roblox removed it
		task.wait(0.2)

		if not Tool.Parent then
			Tool.Parent =
				Player:WaitForChild(
					"Backpack"
				)
		end
	end
)

print(
	"⚡ SPEED SUPERPOWER TOOL CREATED!"
)

print(
	"⚡ STREAK UI ACTIVE!"
)