Simplistic universal fly script

-- ===== Universal Fly Script (R6/R15 Safe) =====
-- Toggle: F
-- Move: W A S D
-- Ascend: Space | Descend: LeftControl

local Players = game:GetService("Players")
local RunService = game:GetService("RunService")
local UserInputService = game:GetService("UserInputService")
local Camera = workspace.CurrentCamera

local player = Players.LocalPlayer
local char = player.Character or player.CharacterAdded:Wait()
local humanoid = char:FindFirstChildOfClass("Humanoid")
local hrp = char:FindFirstChild("HumanoidRootPart") or char:FindFirstChild("Torso") or char:FindFirstChild("UpperTorso")

-- Settings
local TOGGLE_KEY = Enum.KeyCode.F
local Speed = 80
local VerticalSpeed = 60
local MaxForce = 1e5
local AutoAnchor = false

-- Internal state
local Active = false
local bv, bg
local conn
local input = { fwd=false, back=false, left=false, right=false, up=false, down=false }

local function ensureParts()
    if not char or not char.Parent then
        char = player.Character or player.CharacterAdded:Wait()
    end
    humanoid = char:FindFirstChildOfClass("Humanoid")
    hrp = char:FindFirstChild("HumanoidRootPart") or char:FindFirstChild("Torso") or char:FindFirstChild("UpperTorso")
    return hrp ~= nil
end

local function destroyControllers()
    if bv and bv.Parent then pcall(function() bv:Destroy() end) end
    if bg and bg.Parent then pcall(function() bg:Destroy() end) end
    if hrp and AutoAnchor then
        pcall(function() hrp.Anchored = false end)
    end
    bv = nil; bg = nil
end

local function createControllers()
    if not ensureParts() then return end
    destroyControllers()
    if AutoAnchor then
        pcall(function() hrp.Anchored = true end)
        return
    end
    bv = Instance.new("BodyVelocity")
    bv.MaxForce = Vector3.new(MaxForce, MaxForce, MaxForce)
    bv.P = 2000
    bv.Parent = hrp

    bg = Instance.new("BodyGyro")
    bg.MaxTorque = Vector3.new(MaxForce, MaxForce, MaxForce)
    bg.P = 3000
    bg.Parent = hrp
end

local function getMoveVector()
    local mv = Vector3.new(0,0,0)
    if not Camera then return mv end
    local look = Camera.CFrame.LookVector
    local right = Camera.CFrame.RightVector
    if input.fwd then mv = mv + Vector3.new(look.X, 0, look.Z) end
    if input.back then mv = mv - Vector3.new(look.X, 0, look.Z) end
    if input.right then mv = mv + Vector3.new(right.X, 0, right.Z) end
    if input.left then mv = mv - Vector3.new(right.X, 0, right.Z) end
    if mv.Magnitude > 0 then mv = mv.Unit end
    return mv
end

local function startHeartbeat()
    if conn then conn:Disconnect() end
    conn = RunService.Heartbeat:Connect(function()
        if not Active then return end
        if not ensureParts() then return end
        if bg and bv then
            bg.CFrame = CFrame.new(hrp.Position, hrp.Position + Vector3.new(Camera.CFrame.LookVector.X, 0, Camera.CFrame.LookVector.Z))
            local mv = getMoveVector()
            local horiz = mv * Speed
            local vy = 0
            if input.up then vy = VerticalSpeed end
            if input.down then vy = -VerticalSpeed end
            bv.Velocity = Vector3.new(horiz.X, vy, horiz.Z)
        end
    end)
end

local function stopHeartbeat()
    if conn then conn:Disconnect() conn = nil end
end

local function enableFly()
    if Active then return end
    if not ensureParts() then return end
    Active = true
    if humanoid then pcall(function() humanoid.PlatformStand = true end) end
    createControllers()
    startHeartbeat()
end

local function disableFly()
    if not Active then return end
    Active = false
    stopHeartbeat()
    destroyControllers()
    if humanoid then pcall(function() humanoid.PlatformStand = false end) end
end

-- Input handlers
UserInputService.InputBegan:Connect(function(io, gp)
    if gp then return end
    local kc = io.KeyCode
    if kc == TOGGLE_KEY then
        if Active then disableFly() else enableFly() end
    end
    if kc == Enum.KeyCode.W then input.fwd = true end
    if kc == Enum.KeyCode.S then input.back = true end
    if kc == Enum.KeyCode.A then input.left = true end
    if kc == Enum.KeyCode.D then input.right = true end
    if kc == Enum.KeyCode.Space then input.up = true end
    if kc == Enum.KeyCode.LeftControl then input.down = true end
end)

UserInputService.InputEnded:Connect(function(io, gp)
    if gp then return end
    local kc = io.KeyCode
    if kc == Enum.KeyCode.W then input.fwd = false end
    if kc == Enum.KeyCode.S then input.back = false end
    if kc == Enum.KeyCode.A then input.left = false end
    if kc == Enum.KeyCode.D then input.right = false end
    if kc == Enum.KeyCode.Space then input.up = false end
    if kc == Enum.KeyCode.LeftControl then input.down = false end
end)

-- Cleanup
player.CharacterRemoving:Connect(function() disableFly() end)
player.CharacterAdded:Connect(function(c) char = c ensureParts() end)

print("[Universal Fly] Loaded. Press '"..tostring(TOGGLE_KEY.Name).."' to toggle fly.")