I’ve noticed that Roblox has become rampant with trolls doing inappropriate behaviors on a platform composed mostly of a younger audience. I wanted to tackle this problem and created an automatic troll detection and prevention system for Roblox games. This script detects players spamming forward and backward (W/S key spamming) near another player and automatically kicks them after a sustained period. This helps prevent harassment, trolling, and inappropriate behavior in your game.
How the System Works
Detection Mechanism
-
Monitors Movement Direction
- Uses CFrame LookVector to determine if a player is moving forward or backward relative to their current facing direction.
- Uses dot product calculations to assign movement a value:
-
+1= Forward -
-1= Backward -
0= Neither (standing still or moving sideways)
-
-
Detects Rapid Toggling Between Forward and Backward
- If a player rapidly switches between forward and backward movement, the system recognizes this as toggling.
- If toggling continues for longer than
REQUIRED_TOGGLE_TIME, the system registers a detection.
-
Checks if Another Player is in Front
- Uses Raycasting (
Enum.RaycastFilterType.Exclude) to determine if another player’s character is withinCHECK_DISTANCEstuds ahead. - If no player is detected in front, the toggling does not count and resets.
- Uses Raycasting (
-
Tracks Detections and Issues Warnings
- Every time a valid detection occurs, the player’s detection count increases.
- If the detection count is below
DETECTIONS_REQUIRED, a warning is logged, and tracking resets for further offenses.
-
Punishes Offenders
- If the player reaches
DETECTIONS_REQUIRED, they are kicked from the server (default behavior). - The punishment logic is handled by the
PunishPlayerfunction, which can be modified for alternative actions (e.g., bans).
- If the player reaches
Demonstration
Customization Options
You can tweak the following values in the script to adjust sensitivity:
| Setting | Default | Description |
|---|---|---|
REQUIRED_TOGGLE_TIME |
1 |
Time (in seconds) a player must continuously toggle forward/backward near another player before being detected. |
CHECK_DISTANCE |
3 |
Distance (in studs) to check for another player in front of the suspected troll. |
TOGGLE_COOLDOWN |
0.1 |
Minimum time (in seconds) between direction flips to prevent false detections from minor movements. |
DOT_THRESHOLD |
0.4 |
Sensitivity of forward/backward detection. Lower values mean stricter detection of movement changes. |
DETECTIONS_REQUIRED |
1 |
Number of times a player must be detected before they are punished. Allows warnings before action is taken. |
Installation
To integrate this system into your game:
- Open Roblox Studio and navigate to Explorer → ServerScriptService.
- Create a new Script inside ServerScriptService.
- Paste the provided script (see below).
-
Modify detection settings (e.g.,
CHECK_DISTANCE,TOGGLE_COOLDOWN) if needed.
Full Script
local Players = game:GetService("Players")
local RunService = game:GetService("RunService")
-- Configuration values
local REQUIRED_TOGGLE_TIME = 1 -- seconds of continuous toggling while someone is in front
local CHECK_DISTANCE = 3 -- studs in front of character to raycast
local TOGGLE_COOLDOWN = 0.1 -- minimum gap (seconds) between flips to count as new toggle
local DOT_THRESHOLD = 0.4 -- threshold for dot product (forward/backward detection)
local DETECTIONS_REQUIRED = 1 -- number of detections required to punish the player
--------------------------------------------------------------------------------
-- A dictionary to store each player's "monitoring" connection.
-- Key = Player object, Value = a single Heartbeat connection.
--------------------------------------------------------------------------------
local playerConnections = {}
--------------------------------------------------------------------------------
-- 1) Punishment function (kicks player by default).
-- You can modify this to do something else (e.g. ban).
--------------------------------------------------------------------------------
local function PunishPlayer(player: Player)
player:Kick("Trolling detected: Inappropriate forward-backward spamming.")
warn(("Player %s has been kicked for spamming forward-backward."):format(
player.Name
))
end
--------------------------------------------------------------------------------
-- 2) Called every time the script detects a forward-backward spam event
-- that meets the REQUIRED_TOGGLE_TIME. We decide whether to punish or warn.
--------------------------------------------------------------------------------
local function OnDetect(player, detectionCount)
if detectionCount >= DETECTIONS_REQUIRED then
-- If the detection count reaches or exceeds threshold, punish
PunishPlayer(player)
playerConnections[player]:Disconnect()
else
-- Otherwise, just warn (print to console or do something else)
warn(("Player %s has been detected spamming forward-backward (%d/%d)."):format(
player.Name, detectionCount, DETECTIONS_REQUIRED
))
end
end
--------------------------------------------------------------------------------
-- 3) Determines if the character is moving forward, backward, or neither.
-- Returns:
-- +1 -> Forward
-- -1 -> Backward
-- 0 -> Neither strongly forward nor backward
--------------------------------------------------------------------------------
local function GetMovementDirectionMode(rootPart, movementVector, dotThreshold)
local forwardVector = rootPart.CFrame.LookVector
local dot = forwardVector:Dot(movementVector)
if dot > dotThreshold then
return 1 -- forward
elseif dot < -dotThreshold then
return -1 -- backward
else
return 0 -- neither
end
end
--------------------------------------------------------------------------------
-- 4) Checks if direction flipped from forward to backward or backward to forward.
--------------------------------------------------------------------------------
local function DidFlipDirections(oldMode, newMode)
return (oldMode == 1 and newMode == -1) or (oldMode == -1 and newMode == 1)
end
--------------------------------------------------------------------------------
-- 5) Raycast in front of this character to see if another player's character is there.
-- Returns true if a player's Humanoid is detected in front within 'distance' studs.
--------------------------------------------------------------------------------
local function IsPlayerInFront(character, distance)
local humanoid = character:FindFirstChildWhichIsA("Humanoid")
if not humanoid or not humanoid.RootPart then return false end
local origin = humanoid.RootPart.Position
local forwardVector = humanoid.RootPart.CFrame.LookVector
local direction = forwardVector * distance
-- We don't want to hit our own character, so exclude it
local rayParams = RaycastParams.new()
rayParams.FilterDescendantsInstances = {character}
rayParams.FilterType = Enum.RaycastFilterType.Exclude
local rayResult = workspace:Raycast(origin, direction, rayParams)
if rayResult and rayResult.Instance then
local hitPart = rayResult.Instance
local hitCharacter = hitPart:FindFirstAncestorWhichIsA("Model")
if hitCharacter then
local hitHumanoid = hitCharacter:FindFirstChildWhichIsA("Humanoid")
if hitHumanoid then
return true
end
end
end
return false
end
--------------------------------------------------------------------------------
-- 6) Main function that creates and returns a Heartbeat connection for monitoring.
-- Called when the player's Character is added.
-- We store the 'connection' in 'playerConnections'.
--------------------------------------------------------------------------------
local function StartMonitoringCharacter(player, character)
if not character then return nil end
local humanoid = character:FindFirstChildWhichIsA("Humanoid")
if not humanoid or not humanoid.RootPart then return nil end
-- Variables to track toggling
local lastDirectionMode = 0
local isToggling = false
local toggleStartTime = 0
local lastToggleTime = 0
-- NEW: Track how many times this player has been detected
local detectionCount = 0
-- Create a new Heartbeat connection
local connection
connection = RunService.Heartbeat:Connect(function()
-- If the character or humanoid is gone, disconnect
if not character.Parent or humanoid.Health <= 0 then
connection:Disconnect()
return
end
local movementVector = humanoid.MoveDirection
local directionMode = GetMovementDirectionMode(humanoid.RootPart, movementVector, DOT_THRESHOLD)
local flipped = DidFlipDirections(lastDirectionMode, directionMode)
local currentTime = os.clock()
if flipped and (currentTime - lastToggleTime) > TOGGLE_COOLDOWN then
if not isToggling then
isToggling = true
toggleStartTime = currentTime
end
lastToggleTime = currentTime
end
-- If toggling, check if there's a player in front
if isToggling then
local playerInFront = IsPlayerInFront(character, CHECK_DISTANCE)
if playerInFront then
-- If the toggling + player-in-front scenario lasts too long, increment detection
if (currentTime - toggleStartTime) >= REQUIRED_TOGGLE_TIME then
detectionCount += 1
OnDetect(player, detectionCount)
-- If not punished yet, reset toggling as requested
if detectionCount < DETECTIONS_REQUIRED then
isToggling = false
end
end
else
-- No one in front; reset toggling if enough time has passed
if (currentTime - lastToggleTime) > 1 then
isToggling = false
end
end
end
lastDirectionMode = directionMode
end)
return connection
end
--------------------------------------------------------------------------------
-- 7) Listen for Players joining. For each character spawn, ensure we handle
-- the universal dictionary logic: if there's an existing connection,
-- disconnect it before making a new one.
--------------------------------------------------------------------------------
Players.PlayerAdded:Connect(function(player)
player.CharacterAdded:Connect(function(character)
-- If there's already a stored connection for this player, disconnect it
if playerConnections[player] then
playerConnections[player]:Disconnect()
playerConnections[player] = nil
end
-- Create a new monitoring connection for this character
local newConnection = StartMonitoringCharacter(player, character)
playerConnections[player] = newConnection
end)
end)
--------------------------------------------------------------------------------
-- 8) Clean up when a Player leaves. If there's a connection in the dictionary,
-- disconnect it and remove from the dictionary so we don't leak memory.
--------------------------------------------------------------------------------
Players.PlayerRemoving:Connect(function(player)
if playerConnections[player] then
playerConnections[player]:Disconnect()
playerConnections[player] = nil
end
end)
Changelog
Current Release
How to Test
- Run the game in a Local Server in Roblox Studio.
- Move forward and backward rapidly (spam W and S).
- Position another player/NPC in front of you and repeat the movement.
- If spamming continues for more than 1 second, you will be kicked.
Notes & Additional Information
- This system only activates if another player is directly in front of the offender.
- The toggle detection ensures minor movements aren’t falsely flagged.
- The universal dictionary (
playerConnections) prevents memory leaks by ensuring only one active connection per player.
Feedback & Support
Have suggestions, improvements, or found a bug? Feel free to share your thoughts in the comments.