Nozoku Rush is a puzzle game for those who like speed arithmetic. The basic gameplay involves connecting numbered squares to reach zero. Each number subtracts from the last, so if you start with a 5, you can go to a 3 and then a 2. That makes 0. But you couldn't do 5-2-3 because that would equal -1. You can throw 0s in the middle of any string and, of course, the longer the better.

There are two modes of play in Nozoku Rush. The first, appropriately enough, is Rush. Squares continuously fall from the ceiling and you must string them together quickly to keep from reaching the top. Special squares that clear entire rows or briefly freeze time are a huge help. The other is Race, where the screen is always full of squares and you simply try to get as high a score as possible in the allotted amount of time.

If you can see and process these sorts of equations quickly, I can see how this game could be totally addictive. But—and I say this as someone who genuinely enjoyed math and went up through calculus in high school—this game is not for me. The stress of the ceiling or the time limit is enough that I just can't see stuff. But if this sounds like your cup of tea, by all means go for it.