First, let me get the system out of the way. It's JAGS—Just Another Gaming System. You can download JAGS Revised here. Really, it is just another gaming system—nothing special, a touch complicated, and easily replaceable with a minimum of effort since the sections of Wonderland and The Book of Knots that actually mention mechanics are minimal.

Now onto the good stuff, the stuff that comprises the vast majority of the 400-odd pages (!) of this RPG—the setting. First, since I love taglines, here are five of increasing length and aptness from the game text itself:

"JAGS Wonderland is a modern-day roleplaying game of surreal horror."

"JAGS Wonderland is a world book for a reality that is starting to unravel and in the dark spaces where the threads have come apart are candy-colored nightmare eyes. It’s horror in the traditions of the Silent Hill computer games."

“Wonderland is a whole new universe next door to yours and it isn’t a nice neighbour. Wonderland is full of things that go bump in the night and it’s full of madness and it’s looking to come pouring through into our world. It’s coming for a tea party and it’s bringing friends.”

"JAGS Wonderland is a game of horror and madness set in a world shot through with cracks ordinary people can’t see but can still fall into. It’s about the trap doors that exist all around us and even under our feet: the trap doors we walk over, obliviously, every day of our lives. And it’s about the eerie nightmare world that exists at the bottom of the chutes that they empty into when they do snap open and suck us down.’”

"It's the world on the other side of the mirror—the world that pretends to look like ours—that behaves while you're watching it—that's watching you when your back is turned. Wonderland is the world that exists in empty places where no one can see it. It's the universe that's up and about at 3:00 AM. It's twisted and hungry and it knows all about you. It's read your mail, your diary, and your mind. It has your single, missing socks. It's eaten your sister. It's awakening across the globe and getting stronger. Wonderland is what you should be afraid of, instead of the dark."

In JAGS Wonderland, you play a normal person in a world in which a new, incomprehensible affliction called CPD—Cyclic Psychoaffective Disorder—seems to be more and more common. The scary thing about it, though, is that even though it's a mental condition that makes people have visions of the world going mad around them, it seems to be contagious—and multiple affected people in the same place can have "hallucinations" of the same thing.

Truth is, of course, these aren't hallucinations at all. You see, the reality we know is only the surface—Chessboard Zero. But it's breaking. There are new cracks and trapdoors appearing everyday, things leaking up from the seven Chessboards of reality below, and when someone witnesses something impossible, they're infected too—starting their cyclical descent into lower realms. Chessboard One doesn't seem too bad—it looks almost exactly like our world, only everyone around you is crazy—but once you're there, you're sending up a reflection of yourself, someone who looks exactly like you but is totally insane—good luck explaining its actions away when you come back up to "normal" reality. .

From there, the Chessboards only get weirder. If you're unlucky, you might undergo an uncontrolled descent, i.e. falling down the rabbit-hole, into a place as deep as Chessboard Five or Six. That's what Alice did.

Deal with your "illness." Don't get committed. Explore the fantastical, predatory realities below you. Find out the truth. Run from the truth as long as you can. Don't get noticed by something horrible that can follow you back up. See your actions' rippling repercussions across the various levels of reality. Don't go mad. Embrace your madness. Have tea with the Hatter. Kill the Hatter. Get dragged through a mirror. Use what's below as a source of immense power with a terrible price. Hide under your bed. Don't hide under your bed at any cost. Keep your head attached to your neck. Run from the Queen. Become the new Queen. Drink Wonderland. Eat Wonderland. Play JAGS Wonderland.