This includes, talking like an adult to the parties involved, as well as not intentionally ruining other PCs, or GM's work. Examples may include, but is not limited too: Rage quitting, disrespectfully talking about another PC rather than resolve the issue or try to help them, and arguing with a GM's call on their event…. GM fiat is available for a reason in MnM.
That said, this includes us as council, we're just another guy at the table for whoever is running said event and should NOT interfere with it unless the GM at the time wants us too, or there's a blatant violations of the rules as intended.
Please remember, we're all here to have fun, and part of it, is sometimes, stuff happens to your PC that they have to struggle with, from not having the "right" power, to enemies that are tough to kill, or the dice being hateful. That doesn't mean you sublimate and take it out on others… I know we're all a much more mature group than this.
(Thanks to those that are doing the above well, keep up the great work of making EC a fun place!)