It's a pretty good game. You can also go to the Dueling arena and challenge people to duels. if you want to try your luck press ESC then A and at the top in the middle of your screen it will list arena's, use page up and down to select the one you want, the presss enter.
Also if you want to find out if anyone you know is on, type ?find and then the persons name.
if you want to send a message to someone in another arean type :name: then just type your message. You can also press F1 to find more commands etc.
My name is Mr.Wizard, i'll be the one killing you all.. haha