Dyad is one of those wonderful indie titles that's so strange it doesn't even fit easily into an established game genre. Puzzle-racing hybrid is probably the best description one can muster. You play as a particle moving through a cylindrical tube. Steering left or right moves you around the cylinder's boundary and is your only means of steering. Increasing your speed, on the other hand, is not as simple as holding down on an accelerator. Instead, you can hook onto enemies in front of you by pressing X, which will speed you up gradually. If you really want to get moving you'll have to be a bit more skilful. Most levels have two different colors of enemy. Hook onto two enemies of the same color in a row and you'll get a large boost of speed. Once you've built up speed the difficulty comes in trying to continue to hook enemies while not barrelling into them. Collisions aren't the end of the world, since you respawn immediately, but they do slow you down and take up precious seconds.

Avoiding collisions is fairly easy until Dyad introduces grazing and some new enemy types. Grazing acts a lot like the gameplay of Crazy Taxi, whereby you try to pass by an enemy while staying close to them to earn a bonus. Dyad's version of this has nothing to do with money, but instead rewards you with energy for a lance move which springs your particle forward while letting you destroy any enemies you touch. It's a fun risk/reward system that forces you to play dangerously.

Later enemy types have similar systems, like some that charge towards you when you hook onto them but leave a “zipline” in their wake that you can use to accelerate. Obviously if you let the charger hit you you'll slow down, but move too far away from it and it'll be difficult to use the wake the enemy leaves behind. Other enemies require careful timing instead of maneuvering. Triads are large particles with two smaller particles in orbit around them. Hook onto the larger central sphere and you'll be rewarded with a zipline path appearing behind it, but if you hook onto one of the smaller orbiters the entire triad will disappear and you'll lose your chance to accelerate. All of these mechanics mean that during the speed-oriented levels of Dyad, it's all about building up momentum through ziplines and hooking pairs of enemies, and then desperately trying to somehow maintain that speed.

That's not to say that Dyad is always about going as fast as you can, though. One of the best things about Dyad is that the 27 levels don't all have the same objectives. Sure, there are quite a few that introduce a new enemy and then give you a time limit to beat, but there are also levels that force a more deliberate playstyle. These include levels where you don't have infinite lives, so you have to try and travel as far as possible before losing three lives, or levels where you only have one life and your speed is constantly increasing as you desperately try to gain invincibility shields so you can collide with some enemies and slow yourself down before you're vulnerable again. Variations like this are even more common in the trophy levels, which I'll talk about later. I love a title that continues to surprise you as you play through it, and Dyad certainly fits the bill in that respect.

Playing through Dyad's 27 levels took me about two hours, but the fun by no means has to stop there. All but one of these levels has three different modes. Game mode is what you initially play, with a specific objective and three different tiers of success. Beat this mode and you'll unlock remix mode, which lets you play the level without the objective and with a number of different options for visual effects and gameplay options (like turning off collisions or making the level infinite). It's the perfect mode if you just want to get your zen on and let the crazy colors and audio wash over you as you speed through the track.

Maybe you aren't the zen type, though. You need a challenge. This is where trophy levels come in. Beating the game mode with the highest star rating possible unlocks a totally different level with a new and often more difficult objective. Trophy levels are where the designer really played around with the mechanics. Objectives include slowing down your particle to a stop in a certain amount of time by colliding with enemies as much as possible, hooking onto pairs of particles that don't differ by color but instead differ by the sound they make as you select them, and maintaining a certain average speed along a track. Beating these levels is also how you earn all of Dyad's trophies. It's one of the best uses of the trophy/achievement system that I've seen to-date. Trophies are at their best when they give you ideas for new ways to play, or reward you for going the extra mile instead of just giving you an award for something you would have done anyway. Complete all of these levels and you'll be given a platinum trophy, which is rare for a PSN title, but then again if you can beat all of these crazy objectives then you definitely deserve it.

Even if you prefer a challenge you might want to take some time to play those Remix levels just to soak in one of the best and most unique looking PSN titles to-date. While you whiz by all of the other particles, Dyad treats you to crazy psychedelic backgrounds and musical beats that are affected by how you play. Tracks change with your speed and most of the actions add their own musical flair to the beat. Even the main menu is an instrumental toy that you can play with using the right analog stick and the L2 and R2 triggers. For a game where you are more often than not zooming around at break neck speeds, it's amazing that I never noticed any kind of framerate drop, and a true testament to the skill of the developers.

So if you're a scientist who has always day-dreamed about what it's like to be inside a particle accelerator then look no further. On the other hand, in the much more likely scenario that you're just a gamer with a passion for smaller downloadable fun then you should keep an eye out for Dyad as well. You might only get a few hours out of it, but I guarantee it'll keep you guessing during that time.

This review is based on downloadable copy of Dyad for the PlayStation 3, provided by the developer.