Perils of the Surface World compiles the four scenarios and optional rules expansions for Hollow Earth Expedition released to date, bringing them all under one spectacular cover. This PDF is the byproduct of producing the compilation in print.
Layout of each adventure is mainly unchanged, but the background 'old page' look has been dropped in favor of a clean white. No bookmarks or hyperlinks are included, which is a surprise. The table of contents lists the adventure content separately from the attendant rules additions so finding what you want is not hard, it's just not as slick as it could be.
The quality, clarity, and excitement content of the adventure material is very high and for HEX fans old and new, should offer a lot of enjoyment. The rules content, designed as optional add-ons to reflect the specific surface world environments and tones of each adventure is also top-notch.
The four included adventures are: Miracle Stone of the Amazon, Frozen City of Terror, Legacy of the Terra Arcanum, and Five Talons of the Jade Dragon.
The supporting optional rules are: Faith and Miracles, Horror and Infection, New Sorcery Rituals, Vehicles, and Artifacts, and Martial Arts.
This is an incredible value in terms of roleplayed bang for buck for those who do not already have the 4 adventures. The convenience of having them all in one place may also be attractive to those who do.