Some games are easy to review; they immediately answer questions and are easy to assess as to their merits - good or bad. Puzzle game collections, on the other hand, are a bit more complex. Were you, for example, to simply glance at the numbers and draw some conclusions about the relative worth of the title, chances are good you'd come to the wrong conclusion... let me explain.
First up, despite the first part of the name, there's more to Sudoku The Puzzle Game Collection than just Sudoku. In total, there are four puzzles on offer, including Shikaku (numbers and boxes), Hashi (numbers and lines), and Akari (numbers and... light bulbs?). Without exception, the puzzles have merit; they offer a good, escalating challenge, and they have that great mix of "easy to understand" and "hard to master" that makes for oodles of "just one more go" compulsion.
Sudoku, for those that aren't familiar with it, is about figuring out where to place numbers from 1-9 which, thanks to some simple rules, can only be placed in certain places - and it's the figuring out where to place them that you find both the challenge and the thrill. It's a good implementation, with smart highlighting of rows and grids enabling you to play more easily than with paper.
Shikaru is an interesting one, where you must draw boxes that fill the grid, don't overlap and include only one number - which, by no coincidence, also matches the number of grid squares that your box takes up. It's easy to understand and fun to play, although it's hard to imagine how this could work with just pen and paper. Again, the interface works well and provides you good tools to enable you to concentrate on the puzzle, rather than puzzling over the interface.
Hashi is a quirky bridge-building game and is arguably the weakest "puzzle" in the collection. It's simple but lacks much complexity, although it does open up a bit as you get further into it. A fun distraction, sure, but not something that would stand well by itself.
Akari challenges players to place lightbulbs on a grid, according to variously placed numbers, using those bulbs to fill the grid with light, without shining light on another bulb or breaking the rules implied by the numbers. Again, it's easy to learn, but soon challenges the grey matter. The rules here are the loosest, without the clean, unbreakable rules of Sudoku, but again, it's a fun distraction and different enough from the other puzzles in the collection to warrant inclusion.
Visually, you may have guessed if you peeked at the score, it's a bit of a mess. The puzzles themselves are fine, but the extremely limited and utterly pointless inclusion of 3D stands out as awkward and without purpose. Given the drawn-out nature of some of the later puzzles, it would have made sense to leave 3D out and let our 3DS batteries last longer. As it is, slide the slider all the way down and don't bother with it at all.
Elsewhere, the interface outside of the puzzles feels like it's been slammed together by an intern using Macromedia Flash. Everything about it screams indie web game, with layouts and design severely lacking.
With 600 puzzles, there's a lot to keep you going - if the four puzzle types contain enough variety to hold your attention for long enough to justify the $99 price tag. Given it completely fails to use any of the 3DS functionality in any meaningful way, chances are good you'd get a better experience with a DS game, too. It's definitely not for everyone but, if you like the idea of getting lost in Sudoku, and want another couple of puzzle types to experiment with, it might be worth the hefty investment. Just don't expect anything more than that, otherwise you're sure to come away disappointed.