Summary
Pullblox, known as Pushmo in North America, is a game about pulling blocks out of a wall to save children that have become stuck in the blocks. It's a puzzle-platformer, and the children are, in the grand scheme of things, unimportant to the point of the game: solving some pretty damn good puzzles.
This is one of those games where you play it for a little bit and come away saying "now that's a video game".
Working on solving a puzzle in Pullblox.
Gameplay and "story"
You play as some sort of sumo-wrestler-lookin' guy. He works (?) at a park run by an old man, but some sort of rascal has gone and reset all of the Pullblox puzzles, trapping the children who were playing them inside of the blocks. None of this really matters, but it sets up a reason for why your sumo man is doing what he's doing, and it gives each puzzle a goal, though no reasoning and a flag for a goal would have worked just as well.
The real meat of the game is pulling blocks out of a wall and climbing them to find your way to the child trapped in the puzzle. Each block can be pulled out to a maximum distance of three blocks away from the wall. You can jump between blocks, and you can even jump across one-block gaps, which enables the puzzles to pull off some clever tricks. You're able to pull and push blocks while standing to the side or front of them, provided you have enough room to move with the block, but you can't move blocks that you're standing on top of. Pulling out a block with a child trapped inside will free the child, but you must reach the child to save them and complete the level.
Flags, in fact, do appear when replaying a level.
You can hold the L button to rewind time through a fairly long history, allowing you to experiment and fail without penalty. The rewind feature, I think, was really a mandatory inclusion, as this game would quickly go from fun to frustrating without it. The R button allows you to move the camera around the puzzle to see things not currently in your field of vision, and you can also see a visual overview of the puzzle on the bottom screen, as well.
Later in the game, more elements are introduced such as "manholes" which allow you to teleport to a matching manhole and buttons that push all blocks of the same colour as the button out to their maximum distance. These additions really give extra depth to the puzzles, and they're very easy to learn how to use. The game in general, I feel, is easy to learn but insidiously difficult in a pleasing manner.
Manholes open when they have room to, and you can jump into them to reach otherwise-unreachable locations.
The puzzles start extremely simple and easy, and this is one of the only things I have to complain about with the game. The "tutorial" levels last for a ludicrously long time, and if you don't power through them, you could easily bounce off before getting to the actually-challenging puzzles. Fortunately, the easy ones are very quick to solve, but the ceremony of starting and finishing a puzzle probably takes as long as it does to solve one.
Once past the tutorial stage, though, the game finds its stride and offers some fiendishly clever puzzles that often left me obstinately struggling to solve. Most puzzles are fairly quick to solve once you understand what you need to do (or, as is often the case, experimentally moving blocks over and over until something clicks), and this works very well for the Nintendo 3DS platform. It's quick to pick up, solve a puzzle, and then put back down.
If you do end up stuck and needing to stop playing, you can also just close the 3DS to put the console to sleep and resume, which works extremely well for puzzle games like Pullblox. However, there is no way to create a "quick save" or similar, where your state is saved and then automatically resumed when you start the game again. Your only option for keeping your progress mid-puzzle is to put the console to sleep.
Graphics
The graphics are nothing to write home about, as are most 3DS titles. The colours are vibrant and really pop, and nothing is unclear or muddy. Like most 3DS games, some extra anti-aliasing would help, but Pullblox is really par for the course. The visual style is cartoony and pleasing, and it lends itself well to a light-hearted puzzler.
There's not much to say about the graphics here: they get the job done and look good enough that you won't be thinking about them at all.
Audio
One of my major complaints about the game is the audio. The music for puzzles is pleasing enough, but when you've done a hundred puzzles, it does start to become grating. Normal levels have one song, which I would describe as playful and unintrusive. "Mural" levels (levels where the blocks form a picture) have a different song, which I would describe as "like the other song but different".
One of many mural puzzles.
Fortunately, if the songs start getting to you, there is an option to turn off the music separate from sound effects. If you don't care about either, you can just mute the console.
The sound effects, on the other hand, are very nice and very responsive. Sound effects provide extra indication about how far you've pulled out or pushed in a block, for example. They also let you know when an action isn't allowed and when a mechanic becomes available, such as when a manhole cover opens. The sounds aren't the only indicator of these events, but they add another layer of confirmation, which is nice.
Conclusion
The gameplay is what's important for this game, and it's nearly perfect for what it is. The controls work as expected, the mechanics are intuitive, and the puzzles are quite good once you get past the easy tutorial stage. The graphics, story (such that it is), and audio are secondary for this game. They're all fine, and that's all you need for a puzzle-platformer like Pullblox. They do the job and don't get in your way.
I recommend this game. It's extremely engaging and far exceeded my expectations for an eShop game.