Leonard Norman Wein (/wiːn/; June 12, 1948 – September 10, 2017) was an American comic book writer and editor best known for co-creating DC Comics' Swamp Thing and Marvel Comics' Wolverine, and for helping revive the Marvel superhero team the X-Men (including the co-creation of Nightcrawler, Storm, and Colossus). Additionally, he was the editor of Alan Moore and  Dave Gibbons' influential DC miniseries Watchmen.