✓ Accepted answer
If you take a look at the documentation for the MouseClicked event you will read the following.
Parameters:
playerWhoClicked
Type: Player
This indicates that when connecting to the event with a function, the first parameter will be the player that clicks the MouseDetector and not any part (think about, does a player click a MouseDetector with their head, torso, or leg?). That means we won't have to check for a humanoid like you do with the following.
h = part.Parent:FindFirstChild("Humanoid")
if h ~= nil then
Instead, humanoid will be defined relative to the player.
function onClicked(theplayer)
h = theplayer.Character:FindFirstChild("Humanoid")
h.WalkSpeed = 21
script.Parent.Parent.Parent.REDBULL1:Destroy()
end
script.Parent.ClickDetector.MouseClick:connect(onClicked)
P.S You MUST use a Script.
The MouseClick event must be handled by a Script.