I don't know if this is already known but rolling a massive quantities of dices you can freeze game interface for all other player. The game remain freeze, for a specific a player, until the chat is completely up to date. If this time is to long the web page crash and the player will never updated. Sometimes the login action is invalidated too. The GM can solve the problem by sacrificing the entire chat log, but only if still can log in. I have seen that the single roll is limited to 1000 dice (to avoid this problem), but it's easily override this limit with a command like: /roll 1000d6 + 1000d6 + 1000d6 + 1000d6 + 1000d6 + ... I would suggest to check the total number of a command and, if it is out of safety bounds, cancel the entire command for prevent the page freeze. I hope to have been useful and had post this issue in the right place.