From publisher blurb:
Installation 665 is a level 3 Mutant Crawl Classics compatible adventure written by Julian Bernick, host of Spellburn and author of many Goodman Games and 3rd party adventures.
Upon returning to your lake home of Cratertown, the locals complain of dazed villagers paddling their canoes to the shunned island to the west. Even worse, the adventurers' own loved ones are among the missing! The ancient island now houses an alien temple to cosmic chaos, vomiting forth a sickly lightning up into the skies. Only your brave seekers can stop the forces of inhuman evil from translating the remaining life on Terra AD into the writhing howling mass at the center of time and space! Gelatinous horrors, non-Euclidian artifacts, and the anti-Messiah await them!