Thou Shalt Enjoy Thyself, but not to the point where your enjoyment comes at the expense of the enjoyment of others.

This one is kind of a double-edged sword in some cases, as some people have it stuck in their heads that the only way to have fun is to 'Win'.

Unfortunately, everyone can't 'Win' all the time. Being a good loser when the dice (or the schemes) didn't pan out in your favor is a hallmark of a reasonable, mature gamer.

We like reasonable, mature gamers. And really, even if things didn't work out for you this time around, maybe next time!