Tunnelvision and gas

First off Iam the idiot who cooked up the scheme.

So we run a weekly serial esque game with stuff of the week. We where given a job to clear a warehouse of rats. Me the sorceress figured that would take ages so suggested we use gas since last week we had helped a Tabaxi alchemist. So we got a reactive agent and I used fire to heat the liquid into poisonous gas. Before that the gm had given hints that the rats seemed docile and peaceful. So we gassed the warehouse and as we entered after fumigating we where met with the sight of 12 dead humanoids. Apprantly they where all druids who used it as a chillout den. So we hid the bodies in the gator infested sewer and got paid.