The "mystery" or "puzzle" geocache is a unique type of geocache where the cacher usually must do some extra legwork to find the final coordinates, one of which may be the number four.
Some of the area's most prolific puzzle solvers (4 of them come to mind) are of course some of the most prolific puzzle creators as well. Have I created a puzzle here that will stump the best of them? The answer to that question may be found by how many rights and wrongs will show up on certitude.
Some folks are scared off by that blue question mark they see on the map, but many puzzles are quite simple to solve, like this one.
So what do you say, do you want to give this one a try?
The first mystery cache was (is) called Octopus Garden. The cache is on our website maps since it was placed in September of the year 2000. The simple puzzle, created by AdventureTom, started a movement that includes paper and pencil conundrums, online searches for obscure facts, field puzzles, and some of the most epic enigmas in geocaching. It's so old in fact, that many of the hardcore cachers go out of the way to find this one, even though the cache is in North Carolina.
There is a mystery cache that was placed before this, but it was never found and was archived quickly because it was removed by the property owners. I've had at least 5 of my caches archived.
The question mark also now signifies challenge caches as well. Sometimes the challenge to qualify is simple, for instance a cacher may have to have found 500 caches to claim a find on the challenge. Sometimes it's 7 times harder than that, you may have to fill the entire fizzy grid to qualify.
Puzzle caches can also be used for geo-art. The first geo-art I ever found on the map was the "GEOCACHING" geo-art near Sioux Falls, South Dakota. Now also in the same area is the SD pheasant, the smiley face, and the 9x9 grid of "Fick's Fizzy." I also took up the geo-art fun on a small basis, as I have some caches near Hampton, MN in the shape of a number.
One of the big Minnesota geo-artists is Bflentje. He's got the Pac-Man geo-art by Cannon Falls, as well as at least 2 others.
I've always felt that I don't have one creative bone in my body, but I do have a few puzzle caches hidden where the reviews have been positive. But then I won't tell you about the negative reviews I get. 
By July of 2008, I had found 9 puzzle caches, but only one of those is still active. After so many years, it's not really that surprising, I suppose.
At the time I put this puzzle cache together, I had found 3273 mystery caches. I would like to find 5 more, but the ones in my solved pile will have to wait for now. The sun will come up tomorrow, and there will be another opportunity for geocaching.
So that brings us just about to the end of the puzzle. You've probably spent at least six minutes of your time trying to read between the lines and figure out what you need to do.
If you can solve this in one try, give yourself a high five. Good luck!!!