Lots of cool stuff in here. I like the idea of being in a volcano that's also a ticking time bomb! Everything is laid out and easy to digest too. If I had any input, it's that it would be fun to add some activities to go along with the creatures on the encounters table. For example, there are 2d4 Goblin Outcasts but maybe they're up to something like digging up weird volcanic soil roots to gnaw on. Otherwise, nice work!