Basically, the game turns minesweeper-ish gameplay to picross-style pixel image drawing purpose. Instead of clues being along the edges of the game field like in picross, you'll see numbers from 0 to 9 scattered across the field itself. A 0 means that neither the clue square nor the up to 8 surrounding squares is colored with a given color; a 9 means that the clue square and 8 squares around it are all colored the given color. Puzzlers must use logic to solve these clues, clicking with the mouse to mark squares that should be colored. At the bottom left, you can click to change from coloring to marking blanks, or blanks can be marked by holding [shift] while clicking. Multiple squares can be dragged over at once with either method. On the right, you can click the green button or hold [ctrl] to drag the game window around, and use the + and - buttons to make the playing field larger and smaller. Clicking outside the window or the [P] button pauses, and in the options menu you can toggle sound and music, and switch between two visual styles for the game window.
There are certain tricks which the game teaches you in the tutorial level, such as a four in the corner or a six along an edge, but the real challenge and fun of the game is after you've bubbled in all these obvious clues and you start looking for interactions that you've missed. Just like in picross, marking squares blank isn't technically necessary to win, but it's practically indispensable to solving it, especially in mulitcolored levels. In these levels with two or more colors, the key to solving it is to remember that a clue square can only either be its own color or blank, never any of the other colors.
Analysis: While 48 levels is a solid chunk to play, you might wish the available level sizes were a bit larger. Even a level or two each of 20x20, 25x25 and 30x30 levels would have made the game feel more complete, as the hardest free levels available can all easily be completed in less than twenty minutes, some in as little as five minutes. In this respect, at least, Picma Squared does offer the perfect chunk of casual logic puzzle gaming; something that newcomers can cut their teeth on, and veterans can pick up and enjoy a nice cerebral workout for a while.
When you finish a puzzle, aside from the satisfaction of a brain well-exercised, you're rewarded with a pixel-ish art drawing of a palm tree or a dragon. While you can sometimes tell vaguely what a picture is going to depict as you're solving it, it's rarely worthwhile to actually try to fill in the puzzle squares based on what you think should be filled. A single square here or there can totally mess up everything, and when you try to go back to fix it, you have no way to distinguish what was a guess. Best to stick to cold, hard logic here. You will never have to guess. There will always be something you can deduce. You just have to look harder for it.
If you do find yourself burning through the available levels, you might be glad to know that the developer's site offers access to more for a small fee. The subscription method is a little awkward. You have to register to even see what the subscription costs are. However, Picma Squared does provide a win/win solution for those desperate to play more but unwilling or unable to pay out the money to do so. Create a level in the level editor and submit it. If it's approved, you receive two credits which enable you to buy two individual levels, and your level will be available to be played by others. The game makers are aiming for a 48hr or less turnaround for approving levels.
Picma Squared is offering an experience that, especially in the multicolored format, just isn't being offered anywhere else yet. Established fans of picross looking for something new shouldn't miss this, and anyone who likes visual and logic puzzles will probably want to give it a try as well.