In addition to Lewis, Hoffman was assisted in editing by several other writers, included Elmer Davis, Larry Barretto, L. Patrick Greene, J.D. Newsom, William Corcoran and Anthony Rud. Hoffman also created a special "Off-the-trail" section for stories different from the normal type of "Adventure" fiction. These included the science fiction story "The Green Splotches" by T.S. Stribling, a genre "Adventure" did not normally publish. Hoffman also obtained the services of some famous artists to illustrate "Adventure", including Rockwell Kent and Lejaren Hiller, Sr.   Hoffman was co-founder of the Adventurers' Club of New York in 1912. Sinclair Lewis was secretary for several years. Numerous "Adventure" contributors were club members, including H. Bedford-Jones, H. D. Couzens, Captain Dingle, J. Allan Dunn, Lejaren Hiller, Arthur D. Howden-Smith, Hapsburg Liebe, Gordon MacCreagh and Talbot Mundy. In April 1962, the Club's Board of Governors named Hoffman President Emeritus and Honorary Life Member. Concerned about the threat of war, Hoffman set up a committee in 1915 designed to secure pledges from former soldiers whose skills could be used in times of need. The committee was named "The American Legion". The pledges were sent to Washington, where they were used to create two regiments of aircraft mechanics. After the war, the American Legion adopted the name of Hoffman's organisation; Hoffman stated in 1934 that he was "delighted" to give up his claim to the name. Hoffman also edited a companion pulp magazine to "Adventure", "Romance" (1919-1920). "Romance" was aimed at female readers and featured writers from "Adventure" such as Mundy and Stribling, as well as Joseph Conrad, Georgia Wood Pangborn and Beatrice Grimshaw. However, "Romance" was not successful and was cancelled after a year. Writer Lee Server describes "Adventure" under Hoffman's editorship as "inarguably one of the handful of great pulp publications" and magazine historian Mike Ashley states in its that under Hoffman: ""Adventure", along with "Blue Book" and "Argosy", was one of the top three American pulp magazines to which all such authors aspired to contribute." After leaving "Adventure", Hoffman worked as the editor of "McClure's Magazine" before retiring to New York.