Not a mini, but Kurulin Fusion came up in discussion in the news comments.
I picked up Kurulin Fusion on sale last year and for only $2 thought it was great value. It's a very interesting puzzle game that I did enjoy for several months. The core gameplay was solid, and the challenges were varied and enjoyable, but the difficulty made the game feel like pure luck at times.
The soundtrack in Kurulin is good, but not especially lengthy so does get grating after some time.
The graphics are very well done. The blocks all look vibrant, and the animations are surprisngly flashy.
The gameplay can be extemely difficult. In Kurulin you have to fuse blocks and place detonators, matching their corresponding colours. The two sometimes come down together, making it difficult to keep your blocks from clearing. The board itself is fairly small, which makes it very difficult to keep colours seperate. When trying to fuse larger blocks, you usually have to choose just one colour and hope you get enough blocks, as you'll need to clear the other colours to avoid having the board fill.
That being said, the challenges in Kurulin Fusion were extremely enjoyable. Some of the most challenging and rewarding involved needing to clear multiple fused blocks of a certain size. Making larger blocks is extremely difficult. Not only do you need to keep the detonators seperate from your blocks, the blocks themselvs only fuse in regular patterns (1x2,2x2,1x3,2x3,3x3).
The main game is a basic match 3 or tetris style gameplay. The blocks fall eternally, so long as you can keep clearing the space. The downfall is there seems to be little reward to creating larger fusions. I found myself avoiding the risk/reward of the larger fusions, though I've never been one to chase highscores. The only time I actively tried to build a bigger fusion was when the gameplay was beginning to speed up, as you could jump past several levels with a large chain.
The real downfall in the game is the difficulty. Not only does the number of colours increase, but the speed does as well. The speeds seemed to be on a tiered system, increasing by level and then reseting again (I think every 10 levels). This is ok in the main game, since you can plan ahead and leave yourself some easy points to race through the faster speeds. The challenges are tiered in this same fashion, but an entire row of challenges is at each speed. I eventually got stuck and gave up because of this. I'm a big fan of puzzle games and usually continue playing, even if I no longer enjoy the game. The ridiculous speed made these challenges feel like sheer luck.
Overall I would have to give the game a 8. Recommended, but at $4 you may want to look into other puzzle games.