Yeah, I have that four-issue series.
I picked it up after-the-fact in 2002 when I was on a completist Mignola buying spree (along with his complete HELLBOY run, DRACULA movie adaptation, first writer/artist story in LEGENDS OF THE DARK KNIGHT, a single issue of SUPERMAN, and other stuff)
I actually was a little disappointed with this one, because I felt Williamson's inks blunted the quality of Mignola's art, that they were not a great collaborative team.
Two other appearances I like of Fafhrd and Grey Mouser were in
CONAN 6 by Roy Thomas and Barry Smith (an amusing two page meeting with Conan).
And a brief 5-issue run of
SWORD OF SORCERY (1973) by Dennis O'Neil, Howard Chaykin, "Crusty Bunkers" (i.e., Neal Adams and artists of his Continuity studio), Walt Simonson and a few others.
