Up top, this is one of the best looking entries, and it does it without a flashy cover or big, complicated art. The color choices make it feel stormy and slippery. The choices for small spot art are just enough to sell the presentation and orient the reader. The layout feels familiar after reading a bunch of stuff written for OSE. The map is super usable.
I really like how the players' expectations are subverted pretty early into the dungeon. Things are not what they assumed but are also straightforward enough for them to grasp pretty quickly after getting there. I imagine most NPCs are not going to be shy about providing (at least certain kinds) information. I also just love the trope of wizards "solving" problems in ill-advised ways.
Overall, great entry. One of my favorites.