Mantichore began in 2006 and been issued almost quarterly ever since. On a few occasions Blackmore missed a mailing and there were only three numbers issued in a year, however, most years have a full quote of four quarterly issues.
A regular feature in Mantichore is "Mantichorus", a personal introduction which features news of Blackmore's doings, especially publications, in the three months previous to the current issue.
Blackmore has published his own work in the zine (some stories but mainly criticism connected to H. P. Lovecraft, Weird Tales magazine and associated matters).
Mantichore also contains work by many other authors including Margi Curtis, Charles Danny Lovecraft, and others.