Crystal Cave Classic

Contrary to what evolutionists will tell you, I posit that humanity is descended from magpies. If there’s one thing that attracts people, that leads them to steal, kill and lie, or to drop everything and jet off on a fool's errand, it’s shiny stuff.

Just look at video games - they’re absolutely obsessed with gems. Whether it’s collecting gems, raiding tombs for gems, or matching lines of gems, precious stones are clearly held up as the ultimate incentive.

Crystal Cave Classic continues this line of reasoning. Here, your sole task is to collect every single jewel from each self-contained level.

To achieve this you take direct control of a young adventurer, utilising a virtual D-pad to direct her actions.

Your first and rather disconcerting discovery will be that gravity has no effect on your character. Rather than initiating a jump, pressing 'up' causes you to move in that direction as if your limbs were coated in suction pads.

Once you’ve regained your bearings, you find that you must shunt a series of objects around in order to gain access to the titular crystals. These objects can take the form of boulders, which have the nasty habit of crushing you when you dig the dirt away from them (achieved by simply walking through it).

Then there are the glass blocks that break when you run into them or drop boulders onto them and acid vials that melt metallic barriers. There are many more and each is introduced in a lengthy, informative round of tutorials.

It’s a simple concept and one that may remind you of arcade classics such as Dig Dug and Mr Driller, although it doesn’t come together as tightly as either of those greats.

We’ve already mentioned the rather odd movement mechanics, but we should also tell you that the controls feel sticky. Your character moves a single block at a time, so when holding down a direction you can often find yourself scooting further than you intended to. Given the precision required on many levels, this can often lead to botched attempts and frustrating restarts.

The alternative is to tap the virtual D-pad, but this leads to a lurching and stilted game. You learn to live with the controls thanks to the fact that it’s a puzzler rather than a fast-paced platformer, but on levels where enemies are involved and quick manoeuvres are required, it becomes an issue.

Such levels also uncover an issue with the boulders, which topple a little too unpredictably for their own good. As these are your main weapon against enemies, the uncertainty of where and when they’re going to fall proves aggravating.

Beyond such issues, Crystal Cave Classic lacks the kind of polish we’ve come to expect from the best casual puzzlers on the App Store. It’s a rather bland-looking game, with rudimentary animation, character design and textures.

Given that it costs (at the time of writing) £2.39/$3.99, we’d expect a little more sheen for our money. What you do get for your outlay is a decent and sizeable challenge, with seven chapters of increasingly tough block shifting.

By the time you reach the halfway point in the second chapter you’ll already have encountered some pleasantly taxing conundrums - and things only get tougher.

As such, Crystal Cave Classic will appeal most to those after some old-skool puzzling, from a time when solutions weren’t just handed to you on a plate. For those who aren’t swayed by such nostalgic brain-bending, this gem may well be a little too rough to bother with.