I just created an article Chaos discussing the gameplay mechanic, as well as the other aspects of the game the term relates to. Originally it was modeled after the Divine article, however as I continued to work on it I compiled a lot of lore and I'm not sure whether it should all be placed in one article or multiple articles.
First there is the damage stat, which I think is covered adequately in the article.
Then there is the cultural impact of Chaos. Consider the Daughters of Chaos: they took their name from a pre-existing aspect of their world. Also consider Chaos weapons: master blacksmiths of Izalith produced weapons with qualities of Chaos. All of this took place prior to the fall of Izalith, and even before the defeat of the everlasting dragons.
There is also the category of chaos demons. Seeing as how the Bed of Chaos is the source of all demons, I was considered adding a list of chaos demon enemies below the list of chaos weapons. One interesting example is the enigmatic Demon Firesage. This guy was the last student of flame sorcery and also the first demon. The lore doesn't quite explain whether he was both of these things at the same time, or if he was a flame sorcerer first and then transformed into a demon after the creation of Bed of Chaos. I am more inclined to believe the latter, seeing as how the bed of chaos is the source of all demons.
Then I thought that might be a stretch for an article that was originally intended to describe a gameplay mechanic. Perhaps I should consider instead creating sub-categories for the enemies category? Please share any thoughts you might have.