With the Heroes alpha being accessed by random people for a while now, there are certain individuals who are extremely annoying. Calling other people noobs all the time, bossing around, fussing, and, perhaps most importantly, sucking at the game. Losing itself is irritating enough. And sometimes even winning can be spoiled by it was thanks to me you noobs won this game. So thank you, mute button.
I haven't played other mobas much, people who did were telling me that the worst is yet about to start, when thousands of 10-15 year olds will access the game. It's good to know that the mute button will be there for me.
+ Show Spoiler +
I wish I didn't have to use it, though.
In case there's anyone who doesn't know where it is: look on the right side of the stats window




