From the publisher's website:
Fascinating and mysterious, the world of dreams and nightmare are rarely trod by the average adventurer. But for some, dreams are a potent source of prophecy, direction and warning. Unlocking and interpreting the true meaning of dreams can gift an adventurer great advantages on his quest and provides a valuable tool for a GM seeking to subtly guide his PCs on their quest.
Portentous Dreams provides the tools for a GM to craft exciting and evocative (but maddeningly vague) dreams to guide and/or confound the PCs. Also provided are 18 sample dreams, easily customisable for immediate inclusion in almost any campaign!