Comics' Greatest Word was put together for Dark Horse Comics and was three years in the making. It came out in the 1990's in a story arch with the same name. The name Comics' Greatest World is a play on DC Comics World's Greatest Comics. The Story Arch Comics' Greatest World started with three prelude issues in Dark Horse Comics eight, nine, and ten called who is X. The next sixteen issues are four, four issue miniseries that are based in or next to the four major cities in the universe, Golden City, Arcadia, Steel Harbor and a town next to the Vortex called Cinnibar Flats.
Each city or area is represented by a logo. Arcadia for has a balanced scale logo with a circle and a cross through it representing the unbalanced justice system in the city. The Steel Harbor Logo is a chain with a broken link representing it is only a strong as it's weakest link and the steel production of the city. The Golden City has a fist holding a bolt of lightning and the Cinnibar Flats was close to the Vortex so it was represented by an eye in a swirl line background.
The logos became a big sign for the Comics Greatest World Universe and it was not part of other Dark Horse universes like Hell Boy. There were some crossovers but they were not considered part of the same universe. The logos were represented on all of the covers for a period of time telling the reader where the charter was from. As the universe went on however the logo was dropped but the universe continued.
Some of the most famous and wrote about characters from this universe were the Ghost and X from the city of Arcadia.