Dungeon Siege III

He picks up a companion for his quest, a rather stern-looking female Archon mage who uses potent but slow-moving flame spells. This happens via a conversation tree (choices cutely represented by the branches of an actual tree in the interface); Obsidian is known, of course, for its storytelling depth and flexibility, and regards this as the principal element it's bringing to Dungeon Siege III and this normally much more linear and less chatty end of the RPG spectrum.

The Archon acts as a capable AI companion at first, but then a second player presses start and immediately jumps in to control her in co-op, the camera snapping up to a loftier, more isometric-style view to give them both room. Co-op is central to Dungeon Siege III and Obsidian tells us that the game is entirely designed around it - although online multiplayer isn't confirmed yet, and locally it's only possible to control a companion character rather than bring a character of your own into someone else's game.

"We want the game to be about multiplayer, and we want it to be as easy as possible," says lead designer Nathaniel Chapman, noting that his girlfriend would watch him play Mass Effect 2 to follow the story, and wanted to be able to jump in and take control of Tali. Intriguingly, Obsidian is working on multiplayer aspects to the conversation system, too. "Multiplayer and single-player are not two separate games. They're totally integrated. That was a very important point for us," he says.

All the game's enemies and spells or abilities have been designed with the tactical interdependence of the classes in mind, and there are even explicit combos that can be executed by two classes in tandem, using each other's strengths to expose enemy weaknesses by forcing them into certain states. The classes, we're told, are designed for uniqueness over flexibility and will be pretty carefully defined, although you'll naturally still have some choice over skills as you level up.

The Guardian and Archon take on a large skeletal boss who summons crowds of minions in what looks like a fun, relatively tough fight where spatial awareness and crowd management are key. One of them dies and is resurrected by the other; any class can do this by standing next to them and holding the left bumper uninterrupted for a few seconds, Obsidian name-checking Left 4 Dead as an influence on this particular co-op dynamic. At the end of the fight, and the demo, is the one thing you really want to see in an action-RPG: a huge chest full of shiny loot. Yum.

It's all admirably stripped-down and focused. It's also quite a long way from New Vegas and Alpha Protocol. "We've made really big, complicated RPGs," says Urquhart. "One of the other games that we're doing right now is 60,000 lines of dialogue... I don't want to say it's ponderous, that's the wrong word. But it's a different flavour. For Dungeon Siege, it's meant to be fun, with fun boss battles with lots of effects going on and all this crazy loot."

"Dungeon Siege is a fun, pick-up-and-play game and Obsidian makes deep, story-driven RPGs, and we really look at Dungeon Siege III as a hybrid of those two styles of game," adds Chapman. "You're still going to get a story, you're still going to get your companions and have dialogue with all of them - and you're still going to be playing an action-RPG."

There's a middle-ground to be found here: we ask if the game will go to the same extreme lengths as Alpha Protocol in the pursuit of Obsidian's mantra of "choice and consequence". "No, not at all," says Urquhart. "The idea is to have some very specific points in the story where you make these decisions, so you feel like it's your story and not just the story we're forcing down your throat. But we're still doing that," he jokes.

It's a balancing act, no doubt, but there's a considerable prize to be won. Blending fast-paced action gaming with the freedom, scale and intimate involvement in story of Western role-playing is just what's propelled Fallout and Mass Effect to such huge success in recent years.

Doing that in the trad fantasy context, with co-op as an additional hook, makes a lot of sense, and Obsidian strikes all the right notes in this E3 demo. Square Enix's choice looks canny indeed; perhaps this game could see the apprentice step out of its masters' shadows once and for all.