20th Century Fox is making progress with its “X-Men” spinoff, “Deadpool,” and has tapped “Zombieland” scribes Rhett Reese and Paul Wernick to pen the screenplay.Ryan Reynolds will reprise his role as the wisecracking mercenary he portrayed in last year’s “X-Men Origins: Wolverine.” There is no timetable on the Marvel property, though Reynolds has a window after wrapping the “Green Lantern” this summer. Reynolds has been bulking up to play the DC Comics’ hero “Green Lantern,” which starts lensing next month. This means he would already be in superhero shape if the script for “Deadpool” is ready by summer. Reese and Wernick, who wrote “Zombieland,” will stay true to the mythology of “Deadpool” given that Reynolds is a huge fan and protector of the property. The tone of “Deadpool,” which features an antihero as opposed to the more traditional heroic comicbook protagonist, is very similar in tone to “Zombieland.” Lauren Shuler Donner is producing “Deadpool.” Reese and Wernick, high school friends who began collaborating in 2001, most recently sold the pitch “Earth vs. Moon” to Universal Pictures. The pair penned a draft of “Venom” for Sony/Marvel. They are repped by WME.