The volcano is a huge maze inside. The big green dragon is trying as hard as he can to spit fire but is requested to spit fire only once a day and only under certain circumstances. Just like any other. A hard learned set of rules for them, and they have to stick to it if they want to be respected. In fact, the situation gets worse each time one of them wants to enter or leave their room, because it modifies itself depending on his surrounding. It is one of these so called "intelligent" castle and even knows how to speak to you.