I never played The Sentinel as a kid, though I was aware of its existence, so I didn't have a huge nostalgia factor coming to Annwn. I'd had the chance to play an earlier version at the PC Gamer Weekender last year and even without polish it struck me as immensely playable; that promise has been borne out nicely.

The gameplay is simple at heart; absorb energy from the world around you, transmit it to create a new totem to house your spirit (since you're dead and "movement is for the living"), shift your soul into it until you reach a point where you can absorb The Watcher at the peak of an island. Simple, easy manipulation of a grid based map.

The Watcher (also known as "that glowing bastard" "why won't he leave me alone" and "oh god he's coming back") spins on his pedestal. If he sees you, he'll drain your energy so game over if you have nowhere to jump to. Drained energy takes the form of Hounds, statues with limited field of vision that can also drain you. Unless you think fast things can get very nasty, very quickly. Get around them though and you can drain the Hounds, returning your energy to where it should be. IN YOU.

The challenge is ramped up with weather conditions; some islands are covered in snow, others might have a thunderstorm in progress. I have no PROOF that building a massive totem tower in a thunderstorm is a bad thing but I was reluctant to risk the lightning! Additionally, some islands are unstable and start collapsing around you at intervals, while others may be in the dark of night, making long range planning impossible. Combinations of those conditions gave me some distinctly hair-raising moments, as I fled a collapse only so come into full view of the Watcher whose statue was masked by the dark...

Procedurally generated maps keep the game fresh; there are potentially numerous ways to finish each level; some levels contain memory stones which allow you to rebuild your life before death stuck you in this afterlife and there's an experience system that lets you boost your abilities at the cost of energy saved up at the end of levels.

The game isn't perfect; some of the randomisation can throw up the occasional impossibility and artefact (floating tree) and it's well worth tweaking the mouse sensitivity in the main menu to make sure you can get pixel perfect accuracy on the merest corner of a square. Overall, however, the gameplay is solid and challenging, the enemies utter sods and the "one more go" factor strong.

I got a review copy for free; before the evening was done I'd bought a copy as a gift.