From the Introduction:
"Secret Of The Spooky Old Warren" is an adventure module for use with the Quick Start version of Great & Small: The Roleplaying Game Of Animal Fantasy. It is designed for a party of 2 to 5 beginning level (0-level) characters of Tiny Size or smaller. Preferably, these characters are all rabbits, but the Quick Start rules provide options for other species of suitable Size. Whether other species are allowed by the BM, the adventure still works best if the majority of the player characters are rabbits.
Setting: This adventure is written to be as "generic" as possible, so that BMs can tailor it to their own preferences. However, its default setting is the Trucewood Vale, a fantasy realm that would feel familiar to players of the original fantasy roleplaying game. The Vale is populated mostly by intelligent animals suitable to a temperate woodlands or mountain environment similar to that of Southern California. However, it is also a "holy land" of sorts to animals from all over the world, some of whom come to visit on long pilgrimages; thus, just about any land animal could be encountered there. The Vale lies close to the faerie realms, as well, so small longpaw-like fey beings such as brownies and pixies could also be encountered, along with magical beasts like griffins, owlbears, or unicorns. The magic of the Vale provides all that the animals need for basic survival, so predation is largely unknown, and animals live in relative peace with one another. However, the recent arrival of longpaws to the west seems to have awakened an ancient darkness; corrupt animals and monsters have begun to appear in the land, and there are rumors that dragons will return in the near future.
None of these fantasy elements play a direct role in this adventure, however. "Secret Of The Spooky Old Warren" can easily take place in the modern world, or in prehistoric times, or anywhere else the BM can imagine. There are no magical effects from the classic fantasy game encountered in the Warren, though this adventure does make use of the concept of spandrels described in the Characters Quick Start document.