Thenardier does not hide away from the poisonous gas. He's undead, more specifically, an aquatic undead. His vorpal blade begins to glow red, and lightning begins to blast off of it, however, it's just there to look cool for now. The blade glows red. He sees the inside-out bear. ((Seems like something from John Carpenter's The Thing )) He let's the ferret scurry up, and takes out in his left hand, a large gold and copper pistol. Let's figh' then beastie.
Thenardier growls at the thing now, his vorpal blade and magical pistol out. He's fought things like this before, due to living in The Hunting Grounds for a while, once serving in the special service militia in Cylar, (before it was blown to the dust by PC's. ), and from a good thirty years of adventuring. He aims his pistol first, preparing the vorpal blade. AS it sizes up the ferret on his head, and the undead Inspector himself, the vorpal blade begins to glow, causing any undead in the room to become obedient unless they're particularly powerful undead. ((Up to Jacklu!))
He fires the golden pistol as Zefir launches a rocket. Thenardier glares at Zefir, he remembered him from...somewhere...he was sure! But right now, bear-thingy. The gold pistol will launch a small black bullet, but as soon as it enters the beast (If it does), it will explode and unleash a horrible necrotic bone rot, which turns bones into saltwater. Die... Thenardier will start walking toward the beast, his wooden leg clunking.