UPDATE 16TH JUNE: There's been a bit more information released - notably that the game is due 2016. You play as lead character Aloy, an outcast form her relatively primitive tribe. She's off to discover the mysteries of the ruined world and with it her destiny.
She'll be up against it, outgunned (although she took that massive beast down pretty easily didn't she) by an assortment of big dino-bots, little pack-bots and ripe-for-the-picking grazer-bots.
"Of course you won't be hunting unarmed in Horizon Zero Dawn," a PlayStation blog post read. "Aloy is capable of combining natural materials with machine parts to turn them into ingenious weapons, ammunition, traps, and tools."
Guerrilla managing director Hermen Hulst, in an interview with Geoff Keighley, said the idea for the game came when Killzone 3 wrapped. Everyone in the studio pitched in an idea and this one floated.
As mentioned, there's a loot-based system in play and there are RPG mechanics - Hulst called Horizon an action RPG - but we'll hear more about those later.
What about Killzone? "We love Killzone," he answered, cagily. "We're here to talk about Horizon: Zero Dawn."
ORIGINAL STORY 15TH JUNE: Killzone developer Guerrilla Games has announced the new PS4 IP it has been working on as Horizon: Zero Dawn.
It's a third-person action RPG (according to Guerrilla's Twitter account) set generations after an advanced civilisation much like our own (a fair few years from now) is eradicated - yet the technological remnants remains. In the intervening years, nature takes over, which makes for a bright and appealingly colourful game.
Some of the dormant AI takes on a life of its own, machines roaming the overgrown cityscape wildernesses like beasts - like great mechanised dinosaurs.
The character the demo focused on was a female member of a tribe living off the land, using only basic technology - spears and bows. She hides under the broad leaves of bushes before darting out to spike her dog-robot prey, apologising for killing it after, in a way reminiscent of the film Avatar.
The demo culminates in her taking on a tyrannosaurus-like robot in a kind of boss battle. During it we get a look at a radial menu where she chooses the type of arrow used for her bow. Some arrows shock the mechanised beast while others explode - and another fixes ropes on the enemy to tangle it and bring it down.
At one point she even picks up a blown-off gun from the enemy's back to use against it. The beast is finished with a focused shot to its weak, exposed heart.
It's an attractive game of real beauty and satisfying heft.