Dig some of Mike Mignola's work from the days before Hellboy!
The Incredible Hulk #307, 1985 (cover)
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Batgirl Special #1, 1988 (cover)
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Cosmic Odyssey #1 of 4, 1989 (cover and story art)
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Marvel Comics Presents: Cyclops #20, 1989 (cover)
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Wolverine: The Jungle Adventure, 1989/1990 (cover and story art)
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Dark Horse Comics #2, 1992 (cover)
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Batman: Legends of the Dark Knight #54, 1993 (cover and story art)
Actually... I think this book came out just months after Hellboy's debut...
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Program for 2007 Baltimore Comic Con (cover)
post-Hellboy, obviously... from this past September...
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and the man himself, Mike Mignola speaking at the 2007 Baltimore Comic Con
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Download an audio interview with Mike from Wordballoon
hereWordballoon Interview Podcast site
hereMike Mignola bio
hereHELLBOY Official site
here