[Genesis]

So if it's an innate power it's a Toxic attack, with Contact Agent, Area Effect, Cyclic, Side Effects (Hallucinations/Berserker), and Accessibility (Only on mages). The value of that last one depends on how common mages are in the setting - there are guidelines for that with the description of Accessibility, I think. Or you can link Afflictions with the Hallucinations/Berserking, if you'd rather.

Of course, describing it as a chemical weapon suggests it's more like napalm than dragon's breath - if you want it to be commercially available just slap a price on it and let the characters buy it, and never mind with the build.