I didn't find myself thinking of hyperthymesia as I played Extreme Exorcism, because there isn't really much time to think about anything when Extreme Exorcism is going on. As soon as I had finished, however, that's when I thought about hyperthymesia.
And in keeping with the spooky context, hyperthymesia is both a blessing and a curse. Wouldn't it be brilliant to have an amazing memory, eh? Wouldn't it be great if you never forgot anything? Actually, wouldn't it be kind of awful? The world would be filled with your memories, every trip to the shop you had ever taken crowding in when you headed into town, every film you had seen converging as you went to the cinema, as you sat down on the sofa. The world would be filled with ghosts. That's hyperthymesia: a condition that describes people who are unable to forget anything.
Extreme Exorcism allows you to poke at such horrors from a safe distance, though. It's a side-scrolling arena action game, in which you race through cluttered single-screen levels picking up weapons and doing in enemies to earn points. The twist is that every enemy after the first is a ghost - a ghost of your previous movements. Extreme Exorcism is a game about hunting your past selves down before they can give your present self a shoeing.
And it's as delightful and panicky as I've made that sound. It messes with the head, too. Each time you play it, you're worrying about your previous selves - the ghosts of whom are gunning for you without knowing it - but you're also worrying about your future self: how can I get everything done now, without making trouble for myself in a few moment's time? You're basically plotting murders, but allowing wiggle-room so that you can drop in in the near future and plot your own murder. It messes with the head.
All of this is happening at a brisk, double-jump pace, too. I really admire the detailing here: I love the way that you can hold up to three weapons at any point, and that, if you do, you'll find that you also fire all three at once. I love the way that each time you're dropped into a map, you only have to kill the most recent ghost of yourself - you'll spot them, because they're wearing a crown - a decision that, in turn, encourages you to trace closer and closer to your previous movements each time: a strangely recursive process.
Most of all, while Extreme Exorcism is great in multiplayer, I love the way that the central gimmick - using past lives to create present enemies - allows for a single-player game that feels wild and human and filled with surprises. It reminds me of Gyromancer, a brilliant match-three RPG hybrid, that ditched enemy AI in favour of a more elegant system, in which your own wasted moves did you damage.
There's a definite space in the world for games that weaponise past player actions, and past mistakes, in interesting ways. We need more games that really know how to use memories - and ghosts.
Extreme Exorcism will launch on 23rd September on PS4, PS3, Xbox One, Wii U, PC and Mac. It will be priced at €12.99 / $12.99 or your local equivalent.
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