Giodo

Hi guys, My brother is overly obsessed with this game called Ragnarok. And there is no way he wants to stop playing the game. So here goes...I want to block the game from accessing the internet so that he won't be able to play anymore. Help me out! I have already tried blocking it from firewall advance setting, and that does not work. I want to know if there is anyway to block its IP address or something. There must be a better way. Thank you,