['Defying Design' is a bi-weekly GameSetWatch-exclusive column by Jeffrey Matulef analyzing gaming conventions and the pros and cons of breaking them. This week's column explores the emergence of stealth based competitive multiplayer.]

I've always found one of the greatest appeals of video games is their sense of mystery and discovery. That I'm using my wits to delve deeper into a world's secret. As such, I've never taken to most competitive multiplayer games. Simply getting to the end of a round and seeing my stats never felt very fulfilling to me.

At the most recent PAX I played a couple of titles that may still make a believer out of me yet. One was Chris Hecker's Spy Party, a two player game where one player is a spy tasked with carrying out a series of objectives at a party, while the other is a sniper seeking to assassinate them. The other game was Ubisoft Montreal's Assassin's Creed: Brotherhood, where each player is assigned to assassinate another while attempting to blend in with the crowd.

What really appeals to me about both of these games is that there's a layer of ambiguity involved that's generally absent from most multiplayer games where other player's are marked by gamertags floating over their heads. While this transparency is certainly sensible for a team-based shooter or strategy game, it heavily limits the possibilities inherent in the medium.

Spy Party in particular excels at exploring a more opaque style of play. The entire game takes place in one room (though the final version may have multiple levels), but there are several other variables that come into play. The sniper can only take one shot. If they choose the wrong target, the game is over and they lose.

The spy, on the other hand, has a time limit to achieve his goals without drawing attention. The truly brilliant thing is that every action the spy can make is something the NPCs do as well. It takes keen observation to suss out the spy, just as it takes clever misdirection to defuse suspicion.

Playing as a spy I was extremely self-conscious as every action I performed felt obvious. Adding extra stress is that you can see the sniper's laser sight caressing the party goers. I've never felt the same kind of pressure in a stealth game before.

Something like Hitman, for example, would allow you to wear a disguise to infiltrate an enemy party, but the rules governing your cover were rigid and faulty. Take take one wrong step into a restricted area and everyone opens fire on you. Though you had to play cautiously, it ended up mostly being a matter of entering certain areas when guards were looking away.

Spy Party fixes that. Partially because being confined doesn't provide a safe zone, but the biggest difference is that you're trying to throw off the scent of a human opponent. Instead of making really advanced AI, you're instead tasked with emulating simple NPC behavior. You're a man trying to fit in with machines.

Assassin's Creed: Brotherhood employs a similar conceit, but loses the asymmetrical roles. Rather than one person being the spy and the other an assassin, everyone plays both roles as you attempt to take out your target without arousing suspicion from your pursuer. Discovering a random pedestrian is not who they seem just as they're about to do you in is riveting stuff -- more so if you're able to beat them to the punch.

This is a huge step up from the previous single-player only Assassin's Creed titles where you could blend into a group of monks simply by tilting your head down and walking in unison with them. I can't imagine a bouncer alive who would fall for that old routine.

Furthermore, the guards in those games would instantly assume you were an assassin simply for running. The same may be true in multiplayer, but only because NPCs aren't adept at parkour. Amazingly, the multiplayer works not by capitalizing on the player's move set, but rather by reducing it. Instead of focusing on the series' trademark parkour, it encourages players to limit these skills to blend in.

It's based on a real life game where people would meet online, be given another player's identity, then attempt to track them down to "assassinate" them with a squirt gun. It's a brilliant idea, but potentially more embarrassing and silly than many would choose to engage in.

Fellow columnist, Michael Abbott, blogged about this phenomenon where his theatre students were unable to play pretend with their classmates observing. In front of a TV screen, however, you're free to be yourself. Ubisoft was really onto something bringing "assassins" to those too dignified to live-action roleplay in public.

Spy Party and Assassin's Creed: Brotherhood both create a sense of tension and surprise largely absent from the frag-fests we usually see by creating a slower creeping terror as you're hunted by an unseen enemy. You're rewarded not for quick reflexes, but for fierce observation and keeping your wits about you.

Ultimately, both games interest me because the thought of being undercover is one yet to be successfully implemented in a single player game. Perhaps all it needed was a second set of eyes.

[Jeffrey Matulef is a freelance writer for G4TV.com, blogs about games at JumpingMoustache.com and is a regular on the Big Red Potion podcast. You can contact him at jmatulef at gmail dot com.]