You could make the argument that Tetris is the perfect game. This is one of the few Tetris "clones" that I thought did something really cool with the formula. It's not quite as fun as Tetris or the brilliant Tetris Effect (which perfects the formula), but the sand physics is satisfying in the same way that all this sand physics stuff is, while also adding its own unique depth and difficulty. I think the presentation could be better but I didn't care, the gameplay is great.