Dr Reiner Knizia's Brainbenders

So there's this doctor, but not in the medical sense, and he's in this game where you do puzzles. He doesn't actually help you beyond explaining the rules of each puzzle, but he's always on hand to impart friendly advice, and of course he tracks your progress for you. It's genius. How come nobody thought of it before?

Okay, so there's a whiff of plagiarism about Dr Reiner Knizia's Brainbenders, but the resemblance to Dr Kawashima's brain training game is thankfully superficial. Yes, there are puzzles. Yes, there's a 'doctor'. But there's no faux medical claptrap about your mental health in this latest puzzler from developer Razorback, and as a result it borders on being that rarest of things in the puzzle genre: vaguely original.

Dr Knizia – in real life a celebrated boardgame designer making the transition into video games – accompanies you throughout Brainbenders. He dresses for the occasion, donning a tuxedo in the Las Vegas casino, pulling on a ski jacket in the icy wilderness of Greenland, and so on.

When you do well, he reaches behind him and pulls out a medal. In the Bank of England, he sits at the computer and types in the answers for you. If you fail repeatedly, he sneaks you a couple of coins for persistence. He's always there to talk you through the rules of a puzzle. He's never short of a few words of consolation or congratulations. He looks like Jimmy Carr, and his company is agreeable, even though he looks like Jimmy Carr.

I say all this to assuage fears that Dr Reiner Knizia is a cut price Dr Ryuta Kawashima. He isn't, and while Brainbenders is unlikely to create the ripples that Brain Training has created, it's still a solid, likeable, and in places sophisticated game in its own right.

All the good meat is in the World Tour mode in which you get to visit 16 different international cities, four of them initially hidden and unlockable. Aside from the puzzles themselves, this mode hangs on a fairly common but well-implemented system of commerce.

You need to buy your way into most of these cities, with only London, Greenland, Moscow and Mumbai available from the get-go. Every time you complete a puzzle you earn a fee, and each puzzle is playable at five difficulty levels, which you also need to unlock with coins (except the fifth, which opens up automatically when you visit 12 cities).

So, for example, it might cost you 20 coins to open up a city, and then five, ten, and 20 to open the extra difficulty levels, making the total cost 55 coins. At the first level, however, you make four coins each for achieving a bronze, silver, and gold medal, and at the next six, and then eight, and so on, so that the total number of coins available from the city is 120.

You'll struggle to get that many, of course, and Brainbenders' difficulty curve is placed such that you'll have to consider carefully whether you want to spend coins opening a level from which you might not be able to recoup your losses, or whether you want to go for a high level in an easy puzzle before persisting with a puzzle that's giving you grief. It's a familiar mechanic, but it works.

The puzzles themselves are a mixed bag. Some, like Berlin's Enigma machine, are original but not that good; some, like Vegas's variant of poker, are original and excellent; some, like Moscow's tedious version of Pelmanism ('pairs', if you're going to be like that about it) and Sydney's 'Simon says' are old hat; and some, like Beijing's mosaic puzzle, are old hat but fun.

All of this, of course, is a matter of opinion and even though you're unlikely to excel at or particularly enjoy all of the puzzles in Brainbenders, there's bound to be plenty in here for you. Plus the fact that each puzzle contains five difficulty levels adds a surprising amount to the game's variety and depth, since the heightened difficulty generally entails the introduction of new elements and rules.

The locations, meanwhile, each have a national flavour. In London, for instance, you need to balance the accounts at the Bank of England by placing operators in equations. You have '+', '-', '/' and 'x' all ranged across the top of the screen, and below them a set of numbers like, for instance, '10 [ ] 5 [ ] 3 = 15'. With the stylus, you need to first select the appropriate operator for each gap and then plonk it down.

There are far too many to describe them all, but you get the idea.

Alongside the main World Tour mode there's Random Play, in which you play four, eight, or 16 puzzles at random for the greatest high-score. You can store up to 20 puzzles to play individually, at whatever level or location you like, and you can also save your puzzles and share them with DS-owning friends by means of download play.

I know: big deal. Dr Reiner Knizia's Brainbenders isn't much outside its World Tour mode, and within it too many of the 20 puzzles are weak. We don't need another game of spot-the-difference, pairs, or Simon says. Nevertheless, there are some beauties, and the mechanic that strings them all together adds much-needed seasoning. Without it, Brainbenders would be patchy. With the spice, it just about works.