NightSky is the latest paid release from Nicklas Nygren aka Nifflas, the god of ambience. Every single one of his games has that special atmosphere that only he can produce, and NightSky is no exception. It's a stunning piece of work, but you knew that already - you've seen the screenshots and the trailer.

It feels just as fluid and effortless to play as it looks. Guiding that ball around is an absolute breeze, and whenever it goes the wrong way, you know it was your fault. The puzzles are also utterly compelling, holding you by the hand to begin with, then blowing your mind time after time. Again, you most likely have experience with Nicklas' expertise in level design, and NightSky will remind you why he is so highly regarded.

And yet... there are numerous design flaws present, not in the execution itself, but rather in the breaking up of the action. The way levels are divided up can lead to numerous frustrating sections, and occasionally I found myself wishing for a particular world to end. Perhaps various recent indie releases have spoilt me in terms of savepoints and minor punishment, but by the time I'd slogged my way through the final parts of NightSky, I was feeling completely exhausted.

Let's discuss the good first, because in all honesty, I actually feel terrible saying a bad word against this beautiful little thing.

You play as a glowing sphere, capable of rolling either left or right. Simple controls maybe, but NightSky manages to do the most profound, wonderful things with this seemingly docile action. The ball can roll up slanted or curved walls, and fly over jumps to land on solid ground, perhaps dodging a gap or an obstacle. Later on in play, you'll have to navigate around spinning planes, over dangerous bridges and generally be a little more clever.

There's a little more to it than just rolling, mind. The A and S keys are assigned random powers on each set of three screens - so at one point, pressing A might make the ball's controls more sticky, while S will make it super-fast; then at other times, S may invert gravity, allowing the ball to float up to the ceiling and navigate a level via a different approach. Experimenting to see which powers you currently have is all part of the fun.

NightSky also features some fantastic puzzles. Many are iterations of the usual types you'll already be familiar with, but with added ball-rolling - for example, pushing blocks to fill a gap which you can then roll across, or the occasional pinball section, during which you have no direct control over the ball. Certain areas of the game require you press the Enter key to remove or spawn blocks, and these are usually the most interesting to decipher - hence, I don't want to go into too much details and spoil it for you.

The precision of the movement is what makes NightSky such a joy to play. The ball moves exactly as you'd hope, and putting aftertouch on it after a jump, allowing it to change direction as it comes into contact with another surface, is a stroke of genius. It's one of those games that you really wouldn't mind watching someone else play, as it's so beautiful in motion.

Of course, it helps that the game looks gorgeous too, with its polished silhouetted visuals and eye-candy gradient backdrops. Every now and again, you'll escape the shackles of a particularly grueling maze and be left to roll over grassy knolls or sandy dunes, and what a feeling it is. The subtle effects, such as leaves blowing in the breeze or vines dangling from above, are what make Nifflas not just a great designer, but a spectacular one.

NightSky's soundtrack is exactly what you'd expect, and then some. As if you couldn't already feel the wind brushing gently against your face, the rolling strings really set the scene, creating that ambient atmosphere we've all come to know and love - then as the more active levels come into play, the excitement picks up and more instruments get involved. Gorgeous stuff.

Yikes, I've not even mentioned the vehicles yet. Now and again, the ball will be encased in a car, or a trolley, or even an airship, and rolling the ball will move wheels inside the vehicle, causing movement and general awesomeness. Again, it all feels so perfect and playful.

Now, the gushing is over, as the way the game is laid out is far from perfect. Each world is separated into groups of three screens, and while I forgot to count exactly how many levels there are in each world, I would take a guess at ten groups of three, for thirty in total. Here's the issue - if you die on screen number three, then the game sends you back to screen one, and you have to finish off one and two all over again.

For the most part, this isn't too bad. In many cases, the three screens are intertwined in such a way that you need to pass back and forth between them to eventually move past the third. However, there are plenty of situations, especially later in the game, when all three screens feature difficult maneuvers, and it is at this point that the going gets rather frustrating.

So picture this - you spend a minute completing the first screen. It takes you several goes, but you finally manage. Screen two causes you some problems, but annoyingly, each time you die, you get sent back to screen one. So not only do you then have to work your magic on that obstacle again, but you also don't get sufficient practice on the second screen, and inevitably fail again.

When you finally do get past the second screen, there's a third one - and believe it, it isn't fun to fail on that one. It's a vicious cycle. Fortunately, this only really starts to happen far into the game, but it still sucked some of the enjoyment out before the finishing line. Having the option to respawn at the start of each screen, rather than the start of a block of three, would have been must appreciated.

[Update: I had originally gone on to moan that you were forced to complete whole chapters in one go, with no way to save partway through. In fact, the game does save partway through any chapter - it just isn't made clear that it will do so. So yeah, that's shut me up.]
What all my moaning boils down to is 'I really like your game, but can you please let me save after every single room completed please?'. And rather than blame myself for being too whiney and not hardcore enough, I'm going to blame recent platformers such as Limbo, VVVVVV and Super Meat Boy. These games have made me weak. They make me feel like I'm battling through tough situations, when in actual fact, I'm being allowed so many tries in quick succession, that obviously I'm going to beat them eventually.

Yet despite my issues with NightSky, I really must stamp my seal of recommendation on it. With around 300 levels to play through, and then a whole extra 'alternative' difficulty that takes the normal levels and makes them even harder - in other words, there's actually 600 levels in total - you've got several hours of play and beyond.

And you know what? So what if I found it frustrating towards the end - up to that point, I was having an absolute blast. NightSky does things with balls that you never thought possible, and is stunning in motion. How's that for a quote.

NightSky will be available from 6th January 2011. The price is still TBA.