With a POD at the end of the Battle of Stalingrad, Hitler realizes that there is no way possible to either win the War or negotiate any kind of peace where he survives, so he decides to spite the world by making the war as bloody and nightmarish as possible, what strategic and tactical decisions should he make to accomplish this? One possibility that I'm particularly curious about is Hitler deciding to use Sarin and other Nerve Agents, how much could the Germans make and how deadly would it be if Hitler went all out on using it?