Vol.1: Two-part adventure set in Empire City, a twisted mystery full of intrigue and action.
 
Vol.2: Game masters who are stuck for ideas for their Silver Age Sentinels super-hero RPG campaigns need look no further than The Sphinx Engine - a two-part adventure scenario featuring the terrifying Iron Duke, set in Empire City. This 32-page book includes both d20 and Tri-Stat System game write-ups. This adventure is for three to five average-powered characters.