In ancient alchemic texts, the symbol of the Ouroboros - or "tail-eating snake" - represents the cycle of death and renewal.

If, however, a serpent chomps on its own backend in Benjamin Davis's Sushi Snake, it means you've taken a wrong turn somewhere and you need to rethink your strategy.

Sushi Snake is a clever, minimalist puzzle game that puts you in charge of a hungry snake with an appetite for dots, boxes, and other snakes.

Snake bites

Cannibalism is A-OK in Sushi Snake. In fact, you can't get ahead unless you chow down on your fellow reptiles. Every level of the game has dots scattered around it, and your goal is to help Snakey eat them.

The problem is, objects like boxes and other snakes get in the way, and so you have to dispose of them all through relentless eating.

You simply drag your snake by the head to move him around the play field. As he moves, he grows. He also automatically devours whatever is in his way, with a couple of exceptions: Snakey can't eat crates or snakes that are the same colour as his body, and nor, for obvious reasons, can he eat himself.

Reptilian cannibalism

With all these rules and restrictions in place, it soon becomes obvious that clearing levels isn't always as easy as slithering into a hole. Luckily, sushi snakes have two natural talents.

One, they can eat anything that doesn't share their colour (other sushi snakes included). And two, they instantly become the colour of whatever dots they consume. This little act of presto change-o is vital in order to gobble up crates and unwanted occupants taking up room on the game board.

Sushi Snake is addictive and charming, and it's as back-to-basics as a puzzle game can possibly get. There are no stars to collect, no techno soundtrack to drink in, no shiny, bubbly graphics. There's no energy meter, and no option to buy hints and solutions through in-app purchases (woo!).

It's just you and that lump of grey matter in between your ears - though if you get fed up with a level (and you probably will) you can surf back and forth through the others. Clearing puzzles down the line can help you get un-stuck.

It's Whacking Day

If guiding one snake through his dinner time becomes too easy for you, Sushi Snake offers more difficult alternatives.

There are, for instance, levels with multiple snakes that move simultaneously. Whichever challenge you take on, persistence and experimentation will help drive you to success. And if you screw up, don't fret - the game's 'undo' button lets you take as many steps backwards as necessary.

There's no shortage of puzzle games on the App Store, so it's easy enough to miss Sushi Snake - especially since it revels in its low-key delivery. If you're in the mood for a brain-bending game that's challenging, however, make sure to hunt it down.