SAN FRANCISCO – At last year's Game Developers Conference, designer Chris Hecker unveiled a prototype of a new game called SpyParty.

This year, he let me play it.

SpyParty is like nothing else I've ever played. It's an asymmetrical multiplayer game: One player mingles among computer-controlled party guests, attempting to perform sly feats of espionage. The other player watches the action from afar through the sight of a sniper rifle, hoping to pick out the human spy from a roomful of robots, then assassinate him.

Chris Hecker is one of the liveliest, most outspoken personalities in the games industry. His yearly "rants" at GDC are the can't-miss moments of the show. This year, he railed against developers not finishing their game designs. In 2007, he made waves when he called the just-released Wii a "piece of shit."

Until 2009, Hecker worked at Maxis creating Spore. Now, following Electronic Arts layoffs, he's a one-man game development team. Showing me and a friend SpyParty at his hotel room at the W, Hecker talked a mile a minute about his new project, which is still in the early prototype stage of development.

"Games are still in the Wild West, design-wise," he said a followup e-mail. "We really don't know what we're doing yet. In movies, sometime around 1900 somebody realized, 'Hey, we could actually move the camera around while the scene is being filmed,' and that was a revelation."

"We're having those moments in game design these days, and will be for the next 10 or 20 years, and that's incredibly exciting to be involved with as a creative person."

I needed to bring a friend, he'd told me, because the game's learning curve is so steep. Experienced players can easily trounce newbies.

Hecker sat us down in a corner, where two laptops with Xbox 360 controllers hummed silently.

SpyParty begins with the spy player, who first selects his character. The player can chose to slip into a handful of different character models: a guy in a tux, women in a variety of dresses, a rotund chap in a top hat.

The mind game starts immediately, because even on this character-selection screen, the spy is trying to outwit his opponent: Which character do they suspect I'd pick?

The spy player has to complete four tasks to win the game: Plant a bug on the ambassador at the party, make contact with a double agent, move a book from one shelf to another and swap a statue for a different one.

Each of these actions has a "tell," a giveaway that the sniper can pick up on if he is paying attention. In the case of the physical actions, it's a quick character animation. For the double agent bit, it's a secret code phrase – somebody will say the words "banana bread." (Hecker says this is what he was having as a snack when he recorded the audio.)

The sniper has a limited field of vision and one bullet to assassinate his target in this early prototype version of SpyParty.

Screenshots courtesy Chris Hecker

The sniper player needs only to watch and listen, but within the limitations of his faraway vantage point. From afar, the sniper can see the entire party, in the windowed corner of an apartment building. He can see everyone mingle, chat and stroll around the room. But he's too far away to make out the subtle "tells" that can help identify the target. Zooming in with the rifle scope narrows the view, but lets him see what the guests are doing.

My first try as the sniper was easy: All I had to do was watch for the one player that didn't act like a computer-controlled bot. The first time I caught my friend correcting his movements in mid-stride, I knew I had my target.

Later moments behind the trigger weren't so easy, once the spy had figured out how to pretend to be artificial intelligence. I wasted more than a few bullets on wild guesses and longshots. SpyParty gets hard.

Hecker says that his former boss, Sims creator Will Wright, didn't get caught up in analysis paralysis. He just picked a target, fired, and said "Let's go again."

The concept for SpyParty has been kicking around in Hecker's head since 2005, inspired by an Indie Game Jam entry called Dueling Machine. That game took place in a teeming city where one player hunted another with a single bullet.

"It was awesome and tense, and I loved the idea of hiding in plain sight and only having one bullet," said Hecker.

After proving my incompetence as an assassin, I switched into the spy role. It is harrowing. You know you