DUOtris is, much like DUO, a very pretty game. It is highly stylized and vectorized, with clean, bright colors making up the blocks on the playing field. Sharp geometric angles and clean linework help keep the important stuff easily noticed during the frenzied gameplay. There is a pretty heavy motion blur, though, so if that happens to bother your eyes, you may wish to stay away from the game. The sound is passable, but ultimately forgettable, with a generic electronica theme and decent sound effects for the different actions you can perform. But really, why are you paying attention to the sound in a puzzle game? You are supposed to be paying attention to the puzzles!

The gameplay of DUOtris is very simple. Match three or more blocks of the same color together to earn points. The kicker? You are dropping blocks on both sides of the field at once. When you move to the left or right, both blocks move to the left or right. Thankfully, this is not strictly enforced. This mean you can stop one block from moving from side to side while the other one still moves around. This goes the same for vertical movement. If nothing interferes, both blocks will touch ground at the same time. If a match occurs, the blocks will be cleared from the field and all blocks above will shift to the point closest to the center. Note, however, that blocks can not match through the center line. This means if there is a blue block above and below the line, you can't land a blue block next to one of them and get a match. The matches only occur on each individual side.

DUOtris has two modes: Classic and Arcade. Classic is slower and much more relaxing than Arcade, partially due to the larger starting area and lack of power-ups. Arcade has a smaller playing field and includes power-ups in the game, so it is naturally much quicker. There is no significant changes beyond that, though. In both modes you match three or more blocks together, score points, and advance your level. Advancing your level functions the same in both modes: clear blocks and the screen shrinks slightly while a single new color is added to the mix. It may be annoying, but it's how the game increases difficulty without increasing the speed of the blocks. The speed of the game does gradually increase as you go up in level, however, so don't get complacent! Nothing like the insanity of Tetris level 20, but still fast.

The power-ups are fairly standard. There are row, column, and diagonal clearing power-ups that get rid of blocks according to the line that the power-up block is on. There's a color randomizer that flips the colors of all blocks on the field. There's are power-ups that speed up time or slow it down, making the blocks fall faster or slower. These are just a sample of some of the power-ups for you to utilize as you clear the board. Some more advanced strategies involving power-ups utilize them to initiate combos, DUOtrises, or both to rapidly increase score.

Scoring in DUOtris is not complicated at all. You match together blocks. There are a few more advanced strategies that you can use to greatly accelerate your score gain. The two most effective strategies are a DUOtris and a combo. A DUOtris is where both blocks land at the same time and match, netting a good score for the player. It has to be at the same time, or it doesn't count, so one block can't land on, say, a 3-block tower while the other lands on a 2-block tower. A combo is where a match clear triggers another match clear by cascading blocks into each other. Combos are easily the most effective way to score, but can be very hard to pull off due to the dual nature of the game. The hardest thing to do is combo DUOtrises, but if you can, you will garner an incredible amount of points. For those who want to compete with other people in scores, there is an online leaderboard that keeps track of both classic and arcade scores accessible from the main menu.

There are a few complaints about DUOtris. The first is a lack of any kind of multiplayer mode, split-screen or otherwise. It very much plays like a great multiplayer game, especially with the power-ups, which makes it a huge downer that you can't actually directly compete with other players. There's also a lack of other modes in the game. A puzzle mode where the player must clear predetermined puzzles would have been a nice addition, and could be used to accentuate the unique features of having blocks drop from both sides of the field at once. The controls are simple keyboard controls, but the menu has to be navigated using the mouse. Overall, though, DUOtris is an extremely well-realized puzzle game.

DUOtris is a simple game by far. However, it's simplicity belies an addictiveness that will keep puzzle fans hooked. Easy to learn, hard to master gameplay and some incredibly appealing tricked-out graphics make it a must play for just about anybody. You can download DUOtris from the developer's website. Sorry Linux and Mac users, you'll have to emulate this one; there are no ports of DUOtris for other OSes.

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