Koshchei the Deathless (Dark Horse, 2018)

Mignola returns to Hell and to the bizarre folklore that's filled some of his greatest books, reuniting with one of his favorite collaborators, Ben Stenbeck (Frankenstein Underground, Witchfinder: In The Service of Angels, Baltimore). This volumes collects the complete six-issue series plus bonus material. Sent to kill Hellboy by the Baba Yaga in Darkness Calls, Koshchei the Deathless hinted at a long and tragic life before being enslaved to the Russian witch. Now Koshchei relives every horrible act on his road to immortality and beyond, with none other than his one time enemy Hellboy himself--in a bar in Hell.