For all the appeal of an open world – the freedom you feel when gazing across the horizon – sometimes there is nothing more exciting in a videogame than playing a small character standing in front of a giant door, wondering what’s behind it. Ideally, that moment of suspense should be drawn out for several seconds, preferably by an elaborate animation that nudges your anticipation still higher. Geometric Interactive’s puzzle adventure recognises this, and duly supplies your insectoid protagonist with a variety of barriers: some mechanical, some organic, all taking a good few moments to part or unfurl before you can head through. Crucially, though, it understands that such grandeur means little if what lies beyond doesn’t reward both your curiosity and the lengths to which you’ve gone to unlock it. On that front, Cocoon is a triumph.

Gateways of a different kind, however, are its central hook. A little way in, you discover what looks like a seedling, from which you pluck an orange, marble-like orb. Soon after, a shallow circular crater, adorned with a conspicuous radial pattern, doesn’t so much invite as practically demand you place it at its centre. A puddle appears at your feet, and at the push of a button (the only one you use for the game’s duration) you dive into the orb, an exhilarating high-velocity plunge followed by a thumping touchdown. It’s essentially a more dynamic variant on those door-opening animations, a dizzying rush executed so beautifully that it’s one of very few elements of Cocoon that is repeated – and that bears repeating. All the same, each descent (and emergence, since it’s not a one-way trip) is so effortlessly swift, smooth and seamless that by the end of the game you’ve almost come to take it for granted.