Since I've been playing ridiculous numbers of spatial reasoning games recently, I figured why not one more? And so I played (and am now reviewing) Stratum.
In Stratum, the object of the game is to have the most hexes visible (from above the board looking directly down at it) as possible when there are no legal moves remaining. To do this, the players take turns placing their pieces (4-wide hex pieces). When placing a piece, you must finish one row before moving onto the next one. You also cannot leave gaps when covering pieces; finally, you cannot completely cover once piece by placing another one directly above the previous piece. That's it. All the rules. Now you understand the whole game.
Now for the pros of Stratum - gaps! Stratum (to me) is all about making the most useful gaps possible. Whereas all of you "color inside the lines" people will try to make the lowest level be fairly filled so that you have more valid placements on the next level, I'm that guy that puts his first piece in some semi-random place in the middle that prevents you from being able to use about half of the bottom row. The more that I've cut off in this move, the better I feel. I like in Stratum that you have several ways of proactively being able to prevent other players from covering your hexes. There are some other ways of doing this, too, but my favorite way is by forming gaps.
Since the rules to this game are incredibly simple and my personal rule (when I feel like applying it) in reviews is to not be longer than the rules, it's time for the cons.
This may just be because I'm in spatial reasoning overload, but I didn't think the strategy was especially deep in Stratum. Don't get me wrong, there is definitely some strategy in the game, I just don't think it is as deep as that of some of my preferred spatial reasoning games (in case you haven't read all of my other posts, those are currently Yinsh and Dvonn). After a couple times through Stratum, I felt like I could safely move on from the game and not bother to play it again.
Overall, I give Stratum a 6.0/10. It is a respectable spatial reasoning game, and my opinion of you won't go down if you purchase it (because I'll never know - but go ahead and use my link to buy it if you're going to... pretty please.) If I were to recommend a spatial reasoning game, though, this wouldn't be near the top of my list.