Haha, sorry... No ill will was intended.
Yeah, the entire second part of the original post is pulled straight out of Warhammer. "Chaos" is used as a general term to describe the potent, tangible, and "alive" embodiment of evil, turmoil, and other various nastiness. Inside this Chaos (sometimes described as a kind of alternate dimension known as "the Warp" are a number of powerful supernatural beings and forces have sprung up from the eldritch energies there. The most powerful of these are the four primary chaos gods: Slaanesh, lord of sensual stimulation and self-serving excess, Tzeentch, lord of change, mutation and magic, Nurgle, lord of plagues, decay and death, and Khorne, lord of war, blood, and slaughter.
The various terms I use ("Nurglite", "Khornate", "Tzeentchian") are just in reference to the followers of these four powers, who, through their worship, have been changed by their patron deity to better suit their interests. Khorne bestows his followers with a consuming bloodlust, Nurgle infects his faithful with a number of "gifts" (his personally crafted diseases) but numbs them to the pain and discomfort of being afflicted, and Tzeentch grants boons of random mutations and sorcerous magic powers.
And as for items in containers, that's correct to an extent. The reason I brought up the use of water is because I believe there is a specific tag that can be applied to container reagents in a reaction that makes the reaction seek out only containers that contain water. Tarn includes specific tags for the individual things he needs them for, and I think he may have needed water for something (I know there's a tag for containers with lye in them, but that wouldn't make for a very good pastry now would it?).
Although I could type up some first-draft raws as a kind of proof of concept, it wouldn't do a whole heck of a lot of good without testing capabilities. I already know how to type up most everything I've illustrated here, I just don't know how well it would work (but most importantly, I'm wondering why other people haven't done this already), so it's really just a difference of time between the original post and a set of drawn-up raw profiles.
I was mostly just bringing these subjects up as a kind of inspiration for someone else, in case there's a modder out there who would be interested in this sort of idea, but just hadn't thought of it for some reason.
EDIT: Another concept... Napalm, A.K.A. "Sticky Flame" for those who play Dungeon Crawl.
Theoretically speaking, a liquid material with a lower ignite point than heatdam point should burn for a respectably long amount of time, instead of just evaporating or consuming itself instantaneously. Now, the real question is... Do contaminants burn?
If they do, then this paves the way for providing a creature with some sort of breath attack that uses this material. It would get blasted out in a cloud, and would coat everything within that cloud in this substance. The goo, now at rest as a contaminant on some item or creature, would then ignite and heat up the surrounding area.
This would result in having a burning victim who can't get rid of the fire by just taking his clothes off. The contaminant would be stuck to the body itself, and would continue to burn so long as it existed, even if the person had no innately flammable items on them. Interestingly enough, jumping into water would still help people out in this predicament, as hopping into water will override any current contaminants with a water covering on all bodyparts and items. If you're in dry country, however... You're buggered.
Of course, this all rests on the assumption that contaminants can burn, which I suspect they can't. Still though, it would be interesting enough to try out. Add your very own mottled dragons into Dwarf Fortress!