B.p.r.d. The Devil You Know Omnibus

Lovecraftian monsters ravage an apocalyptic earth as the B.P.R.D. fights to save what little of humanity they can. But even Hellboy is not who he once was, and whether anyone survives Varvara and the long-awaited Ragna Rok remains to be seen.
Hellboy, Abe Sapien, Liz Sherman, and other familiar faces from the B.P.R.D. gather one last time to make a final stand for humanity.
Written by Mike Mignola and Scott Allie and brilliantly rendered by artists Laurence Campbell, Christopher Mitten, and Mignola himself, this book collects the end of the B.P.R.D. as we know it. Includes B.P.R.D.: The Devil You Know TPB volumes 1-3 and bonus material.