Anti-Exploit Server Disabling Code Not Working

So, I am working on a very “top-secret” project, but this small snippet of code won’t work.

disable = "idk" 
disablecode = "code1234"                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          

game.Players.PlayerAdded:Connect((function(plr)
    if disable == disablecode then
        print("End")
    else
        print("Incorrect code.")
        game.Workspace:FindFirstChild("Terrain"):Destroy()
    end
end))

Any Ideas why?

You can’t call :Destroy() on the Terrain service. But, you can manually overwrite your terrain with “Air” terrain to delete it regions of it, if that’d achieve the same effect? Something like:
game.Workspace.Terrain:FillRegion(Region3.new(Vector3.new(-256,-128,-256), Vector3.new(256, 128, 256)), 1, Enum.Material.Air)
That’ll remove terrain in-between the points -256,-128,-256 and 256,128,256. If it needs to be larger you may need to define it in chunks as Region3’s can’t be defined over a certain size.
What is this trying to achieve though?