Sudoku-ish game. Very good if you're after a math based puzzler with TONs of levels/puzzles.
Where it adds an interesting twist is in that within that overall sudoku box, certain boxes have been linked together with colours which correspond to a mathematic equation.
At first this makes it easier to speed through and complete each puzzle board you're dealing with... but this game has HUGE amount of variations.
There are various visually themed regions which really don't mean anything other than the level of complexity in that particular region. Each region has several points or levels, like a pathway... and within each of those points you have about 800 puzzles. Overall I think this puzzle has 100k of puzzle boards.
Now, I did say "at first" it can be easy. It does get harder as it moves away from basic addition and subtraction equations, starts making ambiguous "this red equation of squares now shares numbers with a yellow boxed equation".... and then you get an uncoloured board where you can set the colours yourself as a visual aid if you need it.
There is a "par" limit per board if you want to achieve a "pass" so that means undoing blind guesses and other mistakes will cost you dearly if you're horribly useless at maths. If you aim for the minimum par of moves (meaning zero mistakes), at speed mind you, you will find the true challenge in this game.
Each point/level (they have a specific name for this but off the top of my head I can't remember it) has to be played through, I think 11 training puzzles???... before you can unlock the remaining 800 Beginner/Medium/Hard boards for that point as well as the next point/level. You start off with the underwater region and to unlock the next region you only need to go through all the trainer puzzles for each point within your current region to unlock the next. This is pretty painless process if you just want to skim through the easy first couple of regions and unlock the more challenging puzzles of the game...
... but in the end its really all a matter of perspective. The simple puzzles still have alot of value as speed trainers and it can be alittle addictive. Once you start a session and you're into these kinds of puzzles, your plan to do 10 puzzles and then do something else with your time turns into 50... and then you find yourself having run through 100.
The best thing about this is that its not a puzzler that stimulates the brain in an abstract and creative way, it's all genuinely practical mathematical stuff... although it can help speed up abstract logic too.
Check it out on Steam... it's pretty cheap considering the massive range of puzzle/equation variations in the game... wait for it to turn up on special or during Summer/Xmas Steam sale and it's a steal.
One "kinda" bad point I found... the sound gets annoying pretty quick. Turn it off (very easy to do) and listen to some tunes... or sit in silence. Your choice.