From publisher blurb:
a secluded village in the mountains holds the entrance to an old complex of rooms where secrets from the holy church lie dormant. Getting in there can be a difficult task, but the occurrences in the village above it can turn the task deadly impossible.
esoteric and psychedelic themes rain over the cosmic gate. An adventure of weird communion with a consciousness out of your campaign world, and of how religions can be affected by outer realms.
The cosmic gate is AN ADVENTURE FOR OSR GAMES DIRECTLY COMPATIBLE WITH OLD-SCHOOL ESSENTIALS. it can be used during long campaigns or in a one shot. it describes a small secluded setting and a dungeon with religious mysteries. it has several magic items to boost your gaming sessions and valuable treasures to boost the character’s experience level.