Server-Side Fly detection (WITHOUT RAYCASTS)

Resources Community Resources
, ,
#1

Hello everyone, today I will be open sourcing a fly detection that I found in 2022-2023.

It’s a really basic detection without raycast’s, I advise not to kick when detected as it could be falsely flagged.

Before anyone starts replying "Oh welllll I can just play an animation or use vfly to bypass it! :nerd_face: ". I know that it’s easy to bypass, detecting 9 year olds with infinity yield on their phone is still better than nothing.

Anyways, enough talk! Here’s the script :

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

local MaxFlyTime = 1

local function PlayerAdded(plr : Player) : nil
	plr.CharacterAdded:Connect(function(Character : Model)
		if not plr:HasAppearanceLoaded() then
			plr.CharacterAppearanceLoaded:Wait()
		end

		local HRP : BasePart = Character:WaitForChild("HumanoidRootPart")
		local Humanoid : Humanoid = Character:WaitForChild("Humanoid")
		local Animator : Animator = Humanoid:WaitForChild("Animator")

		local Time = 0

		-- Wait for the animate script to load.
		repeat 
			if #Animator:GetPlayingAnimationTracks() == 0 then
				Time = 0
				task.wait()
			else
				Time += task.wait()
			end
		until Time > 3

		local Suspicious = false
		local Detected = false	
		local LastPosition = HRP.Position

		local FlyingTime = 0
		local IsFlying = false

		RunService.PreSimulation:Connect(function(dt)
			if Detected then
				Character:PivotTo(CFrame.new(LastPosition)) 
				return 
			end

			-- This is not a 100% guaranteed fly detection, can be easily bypassed but is still enough to stop some skids.
			if #Animator:GetPlayingAnimationTracks() == 0 then
				Suspicious = true
				FlyingTime += dt
				if FlyingTime >= MaxFlyTime then
					Detected = true
					FlyingTime = 0

					HRP:SetNetworkOwner(nil)
					Character:PivotTo(CFrame.new(LastPosition))
					HRP.Anchored = true
					task.delay(2, function()
						Detected = false
						HRP.Anchored = false
						HRP:SetNetworkOwner(plr)
					end)
				end
			else
				Suspicious = false
			end

			if not Suspicious then
				LastPosition = HRP.Position
			end
		end)
	end)
end

for _, v in Players:GetPlayers() do
	task.spawn(PlayerAdded)
end

Players.PlayerAdded:Connect(PlayerAdded)

Showcase :

2 Likes
#2

For anyone wondering, I used a modified version of infinity yield to make it work with studio (Using xAPI).

Here’s the source : StudioScripts/InfinityYield5.9.4

#3

If you could, can you show you walking around with other people in the game?

#4

What do you mean by that?

blurred

#5

Wouldn’t constant :SetNetworkOwner() calls result in input lag if the player has high ping?

#6

No, SetNetworkOwner is only called when the player is detected, and even then, the HumanoidRootPart is anchored so it doesn’t make a difference.

#7

Oh alright, thanks for the clarification

1 Like
#8

Here you go I guess. Youtube video