When the anomaly appeared at the Earth's core, the Substratum Protocol was initiated. You are the best and brightest scientists we have left, our last hope to stem the apocalypse. You are the Substratum Expedition Team. Descend. Learn. Survive.

Prepare to be Mystified by this expansion to the award-winning TTRPG Flabbergasted! Befuddle, bewitch and bewilder your players as you learn how to craft a mystery-driven campaign to introduce into your Flabbergasted games.