Down the Shadowvein is an OSRIC(tm) module designed for 6-10 adventures of levels 3-5. It is a follow-up adventure for Advanced Adventures #1: Pod-Caverns of the Sinister Shroom, but it can be played alone.
You carefully load your canoes and launch into the fast-moving waters of the underground river named Shadowvein. The Pod-Caverns of the Sinister Shroom behind you, the veracity of the map that is to be your guide into the dark unknown will soon be tested. Hopefully what is written is accurate, but if it is not, your wits, wile, and brawn should serve you well as you journey down the Shadowvein!
Down the Shadowvein picks up where The Pod Caverns of the Sinister Shroom left off, but it can be played by those who have not explored that module. Down the Shadowvein continues in The Mouth of the Shadowvein.