is a month long event which is supposed to bring Myst fans back to the cavern (and, with any hope, bring that CAVCON meter up a bit).
It's also known as Cavern Mysterium, so basically, it's like Mysterium... but online. There even a Q&A with Cyan Worlds CEO Rand Miller (and his brother Robyn was supposed to be there, but cancelled; apparently he's busy getting The Immortal Augustus Gladstone on the market). I'm not sure what else is happening, but it sure sounds fun.
Anyway, why am I posting about this, you might be wondering. There have been tons of MO:UL events that I didn't talk about. Well, good sir. You see; I designed the logo for this year. Take a look:
I think it turned out pretty good; I mean, it's not perfect but considering this is my first time doing this sort of thing... yeah. But anyway, there is it. For more info see this thread.