Number 25 in a Series
Hellboy: Seed of Destruction No.1
Hellboy: Seed of Destruction No.2
Hellboy: Seed of Destruction No.3
Hellboy: Seed of Destruction No.4
Hellboy: The Wolves of Saint August
Hellboy: Wake the Devil No.1
Hellboy: Wake the Devil No.2
Hellboy: Wake the Devil No.3
Hellboy: Wake the Devil No.4
Hellboy: Wake the Devil No.5
Hellboy: The Corpse and the Iron Shoes
Hellboy: Almost Colossus No.1
Hellboy: Almost Colossus No.2
Hellboy: Box Full of Evil No.1
Hellboy: Box Full of Evil No.2
Hellboy: Conqueror Worm No.1
Hellboy: Conqueror Worm No.2
Hellboy: Conqueror Worm No.3
Hellboy: Conqueror Worm No.4
Hellboy: Conqueror Worm No.5
Hellboy: The Third Wish No.1
Hellboy: The Third Wish No.2
Hellboy: The Island No.1
Hellboy: The Island No.2
Hellboy: Makoma or, A Tale Told By a Mummy in the New York Explorers' Club on August 16, 1993 No.1 (of 2)

I have everything through the end of Conqueror Worm in trade paperback collections and the individual issues of The Island and Makoma. The individual issues of The Third Wish have thus far eluded my grasp; so, I think I'll just have to duplicate the material I already own from The Island when it and The Third Wish are collected in the soon-to-be published trade Hellboy: Strange Places. All of these issues were written and drawn by Hellboy creator Mike Mignola, except Makoma, which features art by both Mignola and Richard Corben. The twenty-five issue numbering does not include the eight-issues anthology series Hellboy: Weird Tales (I have Nos.1-4 in trade form and the individual issues Nos.5-8), written and drawn exclusively by non-Mignolas.

Next up after the second issue of Makoma is a new six-issue miniseries Hellboy: Darkness Calls, written by Mignola with art by Duncan Fegredo.

Number 23 in a Series
B.P.R.D.: Hollow Earth No.1
B.P.R.D.: Hollow Earth No.2
B.P.R.D.: Hollow Earth No.3
B.P.R.D.: The Soul of Venice
B.P.R.D.: Dark Waters
B.P.R.D.: There's Something Under My Bed
B.P.R.D.: Night Train
B.P.R.D.: Plague of Frogs No.1
B.P.R.D.: Plague of Frogs No.2
B.P.R.D.: Plague of Frogs No.3
B.P.R.D.: Plague of Frogs No.4
B.P.R.D.: Plague of Frogs No.5
B.P.R.D.: The Dead No.1
B.P.R.D.: The Dead No.2
B.P.R.D.: The Dead No.3
B.P.R.D.: The Dead No.4
B.P.R.D.: The Dead No.5
B.P.R.D.: The Black Flame No.1
B.P.R.D.: The Black Flame No.2
B.P.R.D.: The Black Flame No.3
B.P.R.D.: The Black Flame No.4
B.P.R.D.: The Black Flame No.5
B.P.R.D.: The Black Flame No.6

All of the B.P.R.D. miniseries have been co-authored by Mignola, though he has done none of the interior art (he did the covers for both the issues of both Hollow Earth and The Black Flame). Interestingly, and unlike the Hellboy numbering's exclusion of Weird Tales, the one-shots are included in the B.P.R.D. numbering, even though Mignola neither wrote nor drew those issues. I have all the individual isses except for Hollow Earth and The Soul of Venice, both of which I have in trade form. Included along with Hollow Earth is the uncounted one-shot Abe Sapien: Drums of the Dead.

Plague of Frogs, The Dead, and the just-concluded The Black Flame are all chapters of the same massive story, soon to be continued in B.P.R.D.: The Universal Machine, by the usual suspects of co-writers Mike Mignola and John Arcudi and artist Guy Davis.