Fast Fly script item

wait();

local MaxFlySpeed = 100 -- change this as needed

local UIS = game:GetService("UserInputService")
local LocalPlayer = game:GetService("Players").LocalPlayer
local Torso = (LocalPlayer.Character and LocalPlayer.Character:WaitForChild("Torso"))
local Mouse = LocalPlayer:GetMouse()
local Tool = Instance.new("Tool")
Tool.RequiresHandle = false
Tool.Name = "Fly tool"

assert(Torso.ClassName == "Part", "Yikes! Torso is not a part.")

local ToolUtils do
	ToolUtils = {
		--// Setup Vars
		Enabled = false,
        WindowFocused = true,

        Keys = {},
        InternalVars = {
            FlyForward = 0,
            FlyBackward = 0
        }
	}
end

local ToolEvents do
	Tool.Equipped:connect(function(Mouse)
		ToolUtils.Enabled = true
		Torso.Anchored = true
	end)
	Tool.Unequipped:connect(function(...)
		ToolUtils.Enabled = false
		Torso.Anchored = false
    end)
    UIS.InputBegan:connect(function(input, processedEvent)
        ToolUtils.Keys[input.KeyCode] = true
    end)
    UIS.InputEnded:connect(function(input, processedEvent)
        ToolUtils.Keys[input.KeyCode] = nil
    end)
    UIS.WindowFocusReleased:connect(function()
        ToolUtils.WindowFocused = false
    end)
    UIS.WindowFocused:connect(function()
        ToolUtils.WindowFocused = true
    end)
end

--// Main Event
game:GetService("RunService").RenderStepped:connect(function(...)
	if ToolUtils.WindowFocused and ToolUtils.Enabled then
		if ToolUtils.Keys[Enum.KeyCode.W] then
			if ToolUtils.InternalVars.FlyForward < MaxFlySpeed then
				ToolUtils.InternalVars.FlyForward = ToolUtils.InternalVars.FlyForward + 0.7
			end
		else
			ToolUtils.InternalVars.FlyForward = ToolUtils.InternalVars.FlyForward * 1.0
		end
		if ToolUtils.Keys[Enum.KeyCode.S] then
			if ToolUtils.InternalVars.FlyBackward < MaxFlySpeed then
				ToolUtils.InternalVars.FlyBackward = ToolUtils.InternalVars.FlyBackward + 0.7
			end
		else
			ToolUtils.InternalVars.FlyBackward = ToolUtils.InternalVars.FlyBackward * 1.0
		end

		local Camera = workspace.CurrentCamera
		Torso.CFrame = Torso.CFrame:lerp(
			CFrame.new(Torso.Position, Camera.CFrame.p)
			   * CFrame.Angles(0, math.rad(180), 0)
               * CFrame.new(0, 0, -(ToolUtils.InternalVars.FlyForward - ToolUtils.InternalVars.FlyBackward))
			   * CFrame.Angles(-(math.rad(10 * (ToolUtils.InternalVars.FlyForward / MaxFlySpeed)) - math.rad(10 * (ToolUtils.InternalVars.FlyBackward / MaxFlySpeed))), 0, 0)
		, 0.9)
	end
end)

Tool.Parent = LocalPlayer:findFirstChild("Backpack") or Instance.new("Backpack", LocalPlayer)