About B.P.R.D.: War on Frogs
*Mike Mignola's Hellboy spin-off, the Bureau for Paranormal Research and Defense (B.P.R.D.), was generally published as a series of one-shots and mini-series, usually with a single creative team for self-contained story arcs. The War of Frogs differed from this in a few regards. The four issues of the series were treated like one-shots, with differing story focus and creative teams. Some of the artists, such as John Severin and Herb Trimpe, were called in from semi-retirement. This may have contributed to the last difference of the series. Usually, only one B.P.R.D series would be ongoing at a time. The War of Frogs, however, was released over a protracted amount of time, likely related to the artists' ability to turn out work. As a result, there were two other B.P.R.D. titles released concurrently, The Warning and The Black Goddess. Mignola instituted a comprehensive numbering scheme to his B.P.R.D. stories. (He has done this with his other titles as well.) The numbers assigned to the War of Frogs issues are based on their release dates, not some logic of the sequence of the stories, and hence are not consecutive. *Source: Warlock