You've heard of Monaco right? The game caused a huge stir in 2010 when it won the Grand Prize and the

Excellence in Design award at the IGF, despite having only started life a couple of months before the competition's entry deadline. Shortly afterwards, the game's developer Pocketwatch Games -- aka all-round nice guy Andy Schatz -- moved into the shadows to more privately concentrate on his stealth-based co-op title.

Doing stealth the Monaco way

Shortly afterwards, the game's developer Pocketwatch Games -- aka all-round nice guy Andy Schatz -- moved into the shadows to more privately concentrate on his stealth-based co-op title. Now, following successful public showings and the start of a closed beta period, Schatz is gearing up to show the world the fruits of his last few years of labor.

With so much experience working on a stealth game now under his belt, Schatz is more than happy to share his findings -- although the revelation that he has never played any of the Deus Ex games, nor any of the Metal Gear s, will surely see him being burned at the video game stake.

"I've actually missed out on many of the games in the stealth canon," he admits, "but their influence permeates our industry. The question marks over the heads of the guards in Monaco clearly come from the genetic history of stealth games, even if I don't specifically recall being inspired by MGS ."

According to Schatz, there are two major types of stealth game, and it's important to know which you're aiming for: stealth puzzle games, and open-ended stealth simulations.

"Of the stealth puzzle games, I've always felt Hitman succeeds best in making the player feel smart when they discover the almost impossibly convoluted solutions to their Silent Assassin rating," he says. "The feeling of solving those missions is almost the same as some of the harder puzzles back in the old Sierra days."

The rest of the simulation elements of Hitman , however, don't do anything for the Monaco dev. Assassin's Creed: Brotherhood , on the other hand, "succeeds incredibly well as an open-ended 'stealth' game that truly gives the thrill and fear of playing a real like game of hide-and-seek. I can't think of any other game that allows for as human a competition inside a fully formed gameworld (aside from perhaps SpyParty !)"

Balancing is a seriously tricky business when it comes to stealth-based action, and Schatz knows this all too well. While he is looking to encourage players to use stealth and careful planning in Monaco , he acknowledges that a lot of leeway is required from the get-go.

"The early levels of Monaco are actually quite forgiving in this regard," he adds. "We found that the hardest teaching challenge that we faced was that players didn't know how to escape from guards once they were caught. So in the first fifth of the game, we don't punish the player too heavily for it."

He continues, "The guards in this early ramp-up period don't have guns, so while they are a threat, the player almost always can find a way to escape. But once we introduce guards with guns, dogs that track your scent, and turret that fire instantly upon tripping security, we clearly ask the player to watch their step a little more closely."

This balancing act has also caused Schatz to remove entire portions of the game, in order to strip the experience down to just the elements that work.

"The biggest one was a cops vs robbers mode," he explains. "We discovered, after implementing it, that adding a player controlled cop to the existing AI of a level forced us to deal with game balance, which in a single-sided co-op game, doesn't matter as much. In order to keep that mode, we were going to have to build entirely new levels in order to support it. I'd still like to do it at some point in the future, because the act of playing detective and trying to pick up clues about the whereabouts of the enemy was really fun."

For other devs out there who are planning to implement stealth-based play into their games, Schatz suggests looking at the style of choices you are providing players with.

"One of the things I think Mark of the Ninja does really well (and Monaco does relatively well) is that all the information and choices presented to the player are state-based," he notes. "They are digital choices, not analog."

"Players tend to have a hard time making choices based upon a range of values, but if you give them the choice of A, B, or C, they have a much easier time strategizing about the optimal path forwards. Analog values like lighting conditions are usually bad, but digital choices like 'light OR shadow' are good."