Thorfinn's Tomb

Publisher's blurb:

The Ghoul King has arisen once more, and must be destroyed before regaining his full strength. As such, the players have been tasked with the retrieval of Thorfinn's Trident - it being one of the few weapons capable of destroying the undead menace, and preventing him from rising again.

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This (system neutral) fantasy adventure is a simple (self-contained) one-shot, that should be suitable for keeping your players entertained for a single evening's play.

It's designed with starting/low-level characters in mind, and (if printed on both sides of a sheet of paper) can be folded into a handy tri-fold pamphlet/leaflet.