The dilemma I face with Chaos is that the setting and background is pretty lurid. This is certainly not a game for young children and for same families it may be inappropriate for any aged player. I think the reason I find the game acceptable is that the story is so completely over-the-top that it becomes hard to take seriously. I find video games like Modern Warfare troubling because they seem to blur the line between fantasy and reality. Chaos falls more into the category of a Conan novel- taken literally it's quite inappropriate but something about the presentation just seems less troubling.
That being said, the game is set in the Warhammer universe's Old World. The players compete to corrupt and ruin areas using magical powers specific to whichever Chaos demon they are playing. They may fail as a group and the Old World survives to fight another day. Or they may succeed and one player will score the most points and win the game.
Given the lurid and colorful nature of this game one might wonder why it's worth mentioning. For one, it's a very well balanced and designed game. Each demon has special powers that make it very different in play. The players have many opportunities to oppose their competition and the game rewards people who pay attention rather than playing "group solitaire" as some modern games can run to. I enjoyed tthe game's narrative nature- you get the sense of an epic struggle sweeping across continents and lands. And finally, there are enough random events to ensure lots of replay value.
Secondly, Chaos is in the end a fun game to play. Many games have well designed rules. Chaos offers you an experience that is horrifying in reality but oddly entertaining on a game board. I would feel uncomfortable playing Pandemic (a game about global illness) and yet playing Nurgle, Demon God of Plague, was a hoot.
Chaos in the Old World is clearly not for everyone. I think it's a great choice for people who have already gamed in the Warhammer world. I think it's a fun game for older teens and adults who can separate game from reality and who don't find the game concepts deal breakers. So for that population this is a game well worth checking out.