From the publisher's blurb:
Wormskin explores the mythic forest called Dolmenwood, a weird folklore setting for use with B/X or similar tabletop adventure games. Each issue uncovers various elements of this eldritch realm situated on the leafy verges of Fairy, where austere Drunes rub elbows with weird elf-lords and talking beasts, where witches wander skyclad and armed with sinister magicks to bind the spirits of hapless adventurers. Be wary.
Issue 4 includes:
A lakeside adventure locale: the Atacorn's Retreat, wherein the Atacorn Farthigny, spawn of the Nag-Lord, may be encountered.
A d30 generator table for the many lesser standing stones that litter the wood.
A brief exposition of the use of fairy trinkets by those of mortal birth.
The second (and final) part of the Ruined Abbey dungeon, in which the secrets and horrors of the crypts beneath the chapel are detailed.