Question: Code of the Clans is a field guide in a novel series written by a group of authors that collectively use what pseudonym? 
Sentence (from "Code of the Clans"): Code of the Clans is about the Warrior code and includes an ominous sign from StarClan that signaled the need to patrol borders, the unexpected help from a warrior ancestor that cemented the importance of elders, a secret coup that led to a deputy's new role, a medicine cat's pleas that stopped a spree of inner Clan bloodshed and many more stories.
Relevant evidence: No