Really borderline on this one, very close to giving it a negative review, but I am feeling generous. In short, it is an interesting concept, poorly executed, leaving me with a feeling that it is not complete.
It is very much a maze building TD game, something people can love or hate.
There is only one map, though several levels of difficulty. The map has a handful of checkpoints which the foes must touch in order before leaving.
Every fourth wave is fliers, however, which ignore the maze, so you do need to try and keep your maze near the base path, which the fliers will follow.
There is also a boss.
These three seem to be the only monster types however, which is a bit weak.
The core mechanism is that you lay five gems at the start of each turn, but only keep one of them, converting the others to powerless stones which form the maze, along with the gems.
There are a good number of gem types, and each gem has several levels of quality, topped off at perfection. (There is actually one higher, great, but these are very rare, requiring you to get two perfect in the same turn, and combining them. It is almost always worth it though.)
In addition you can combine certain gem types into even higher quality and more powerful gems.
After you have dropped all five gems, open the recipe book to see what you are building towards.
The gems you just received will show as either red if it is the only one you have of that type, or yellow if you have more.
Sometimes you will need to reduce a gems quality to fit the recipe, but you can only do this on the turn you get it, so you do need to be observant.
Once you have all of the gems you need to make a recipe, the map will show which gems can be transformed into the new one, so you have to examine the map looking for the gems with the sparkles floating around them to decide where you want the new one to be.
The other two will turn back into rocks.
All of this adds up to a fairly decent core game mechanic, but somewhat limited feeling.
In addition there are no tactical options, so once a wave begins, you can only sit and watch, always a negative for me.
In addition, there isn't much to spend money on.
Once I maxed out the potential for better quality gems, money just sat there for the most part. In fact lives are interesting in that you can max them out at 100, and increase them during play, so if a bunch of critters get thru, you can click as they first few enter, and get your lives back high enough to survive before the rest show up.
Lastly the game lacks fluff, no story to draw you along. This is sad, as it is the simplest way to generate a player investment, taking zero technical skill really, and it adds so much.
The game has only one speed (another negative) and no real goal, you just play till you die, or hit level 71 it seems. (another negative.) Once you win, it's over, blah.
The controls work well enough, though there are no options that I could find. Can't change the volume of the repetitive but very much in the background sound, or see what keys do what to the map. (Some apparently rotate it, some zoom in and out, but so does the mouse wheel) and no changing the resolution. You get tiny window or full screen.
I got this on sale, half a buck, at that price probably worth a try. Maybe even a deal at a buck, or even two. More than that, I would give it a pass.
ADDENDUM: I would warn people that is it not a quick game, and there is no way to save a game once you start it. Expect to spend an hour or even two, to complete, win or lose.
NOTE: If you wish to learn more, I have created a guide.
ADDENDUM: 14.6 hours before I got bored and put it away.
