(Vortex), #145-147 (Ghost) A Ghost story was featured in A Decade of Dark Horse #2. Also, the Nexus story in A Decade of Dark Horse #3 featured theme park rides of Ghost and Barb Wire, and Hero Zero made a cameo appearance in a story in The Mask. Collected editions During the initial publication period, a black-covered trade paperback was given to retailers as an ordering incentive during the fourth week of each month in the 16-week period. The covers featured the embossed foil logo of the city they represented. Dark Horse has published a handful of Comics' Greatest World/Dark Horse Heroes titles in omnibus form. Dark Horse Heroes Omnibus, Vol. 1 – Collects the Comics' Greatest World and Will to Power maxi-series, plus a written summary of the events in between by Chris Warner (January 2008, ). X Omnibus, Vol. 1 – Collects X #1-11, X: One Shot to the Head, "Welcome to the Jungle" from Dark Horse Comics #19-20, X: Hero Illustrated Special #1-2 (May 2008, ). X Omnibus, Vol. 2 – Collects X #12-25, "Someone to Watch Over Me" from Dark Horse Extra #28-31 (August 2008, ). Barb Wire Omnibus, Vol. 1 – Collects all the original Dark Horse Barb Wire tales, including the Ace of Spades series (September 2008, ). Ghost Omnibus, Vol. 1 – Collects Ghost #1-12, Ghost Special #1, "Sweet Things" from Decade of Dark Horse #2 (October 2008, ). Crossovers Godzilla (with Hero Zero) Nexus (with Vortex; title canceled before release) Predator (with X, Ghost, Motorhead, Agents of Law) The Shadow (with Ghost) Hellboy (with Ghost) Batgirl (with Ghost) The Mask (with all characters and locations) References External links Comics' Greatest World at the International Superheroes directory Dark Horse Comics imprints Dark Horse Comics titles