Most gamers take color in video games for granted. Not only is it used to bring rich worlds to life, but especially with puzzle games, color is also used as an indicator, something to allow gamers to recognize a puzzle and plug in the right response to pass it. We see these colors every day, and think little about them while playing the games. But for the color-blind, these games can be totally different experiences. Some may not be playable at all, while others force gamers with this affliction to play in a different fashion than everyone else.

I should start by saying that I'm not colorblind, which is why I find the affliction of one of my friends even more fascinating. Both he and his brother, as well as another close friend, are all color-blind - not in the black-and-white only sense, but they have trouble differentiating certain colors, blues from greens, for instance. It makes for a good laugh sometimes when the wrong pieces are doled out in Trivial Pursuit, but what I find intriguing is how it affects his ability to play video games.

For most games, the problem doesn't present him any noticeable problems. But go back and look carefully as how color plays a role in certain games - especially the casually popular puzzle titles - and it becomes apparent how difficult some things can be for him.

I stopped over by his house one day last year to see him playing Shadow Complex for Xbox Live Arcade. Many of the game's passages are unlocked with color cues. A red door requires a rocket blast, for instance, while a purple barrier is weak to foam. I watched as he tried blasting a green door with just about everything in his arsenal but the grenades (which is what it takes to open the green doors). Not really thinking about it, I asked why he wasn't just using a grenade. He didn't realize it was green. It did not make the game impossible for him to play, but he wasted a lot of ammo on the trial and error of finding his way through the complex.

The latest problem he has encountered is with BioShock 2. Turrets and vending machines were hacked in the first game by a Pipe Dream sort of mini-game. BioShock 2 switches that up, however, requiring players to stop a needle along a spectrum of colors that has blue, green, white and red. Green means success, while red means sounding an alarm. Blue gives a reward, but white shocks the character. But it all looks too similar to differentiate for him, so it has become more of a game of memorizing the patterns of the machines he's finding. He can get through the game this way, but he doesn't really have a fair shot at completing the puzzles the way everyone else does.

Now I'm not trying to say game developers need to cater to every affliction around, making a game so barebones and politically correct that it can be played by even people totally blind or without fingers. Unfortunately, any disability means certain things in life are going to be harder, including games. But it's interesting to look at which developers have found interesting ways around the small group of gamers who are color-blind, and how other games remain painfully unplayable.

Some would think puzzle games would be the worst for color-blind gamers, as matching and stacking colors is no easy task for someone who can't differentiate between them. Watching any of these friends playing Puzzle Fighter at the arcade makes it apparent they're just stacking and guessing.

But some developers are wising up and realizing it is not that hard to make the game more accessible. While there are still plenty of titles like Table Tennis that hinge on color recognition for gamers' survival, PopCap has worked devices into its games to help those with the affliction. Peggle is based on blue, orange, purple and green pegs, which could be a nightmare for the color-blind. But they've added a colorblind mode that enhances the brightness of certain colors, and also adds small symbols like triangles and plus signs to the special pieces to help gamers differentiate in a way other than color. Games like Guitar Hero, despite their color cues, also keep things ordered in a certain way that makes color recognition less than a necessity.

While the numbers of color-blind gamers may seem small (reports indicate less than 10 percent of men and even less women are afflicted), publishers are likely talking hundreds of thousands for a title like Bioshock 2, it seems catering to an 8 percent crowd might not be a bad idea. It also seems the solutions to the problems in most cases are simple. Peggle makes that obvious. It wouldn't be difficult for a developer to add a symbol to the ball in Table Tennis, or make certain bars longer than others on the spectrum in BioShock 2. Again, it's hard to cater to everyone, and maybe developers are worried about such symbols killing the aesthetics of the game or adding time to development, but it could always be a menu option, or a patch added to the game. And no one should be left without the joy of playing a game like Peggle.

Note: I'm interested in hearing from other colorblind gamers on this issue. What games are impossible, difficult or cater to your affliction in a good way? What other disabilities plague your gaming experiences?