I just caught this on DVD and even though I had heard it wasn't great, I still found it shockingly bad. del Toro's movies did just about everything better. The special effects here looked terrible, the characters weren't interesting, the story wasn't very coherent, and, worst of all, it was boring.
I love David Harbour, but his Hellboy was unappealing. And the relationship between him and Ian McShane as his adoptive father wasn't convincing.
I enjoyed Neil Marshall's Dog Soldiers and The Descent, so expected this to at least be watchable. I don't understand how it went so wrong.