From the product description:
In anticipation for the upcoming Age of Lords Campaign Setting and Age of Lords Expedition Guide, Blackbyrne Publishing is releasing Secret of the Pit as a FREE primer for an adventure set in our world of Thallorand. Secret of the Pit not only provides a free adventure, with our trademark 1" battlemaps, it gives both the GM and the player a glimpse into the upcoming Age of Lords setting. For the GM, there is a Thallorand based primer for bringing new 1st level players together with the cliché standbys. For players, there is a two level preview for the new class Blade Conjuror, which will be detailed exclusively in the Expedition Guide.
AS A BONUS: If you download this before the June (exact date TBA) release, you will get a link for an ADDITIONAL 10% off the sale price of BOTH the Age of Lords Campaign Setting and the Age of Lords Expedition Guide the day of their release!