Question: Which film that Ed Harris performed in included a sniper's duel?
Context: Appaloosa is a 2008 American Western film based on the 2005 novel "Appaloosa" by crime writer Robert B. Parker.  Directed by Ed Harris and co-written by Harris and Robert Knott, "Appaloosa" stars Harris alongside Viggo Mortensen, Renée Zellweger and Jeremy Irons.  The film premiered at 2008 Toronto International Film Festival and was released in selected cities on September 19, 2008, then expanded into wide-release on October 3, 2008. Running Mates is a 1992 American political comedy/drama television film directed by Michael Lindsay-Hogg and starring Diane Keaton, Ed Harris, Ed Begley Jr., and Ben Masters.  The film follows the presidential election campaign of Senator Hugh Hathaway, who faces scandal and controversy when his enemies share secrets of Aggie Snow, the woman he is with. Planes: Fire & Rescue is a 2014 American 3D computer-animated comedy-adventure film.  It is a sequel to the 2013 film "Planes", a spin-off of Pixar's "Cars" franchise.  Produced by DisneyToon Studios, it was theatrically released by Walt Disney Pictures on July 18, 2014.  Dane Cook, Stacy Keach, Brad Garrett, Teri Hatcher, Danny Mann, and Cedric the Entertainer reprised their roles of Dusty Crophopper, Skipper, Chug, Dottie, Sparky, and Leadbottom, respectively.  New cast members included Hal Holbrook, Julie Bowen, Ed Harris, Regina King, Wes Studi, and Dale Dye. Rae Valentine (a.k.a. Harold Ray Brown II) is the son of Harold Ray Brown Sr., the founder and original drummer of the musical band War.  Rae produced and recorded on War's 1994 "Peace Sign" album and performed on tour as backing keyboards, percussion and vocals from 1993 to 2001.  Rae is also an actor who appeared in "Running Mates" (1992) starring Diane Keaton and Ed Harris, "The Family Man" (2000) starring Nicolas Cage and "Sniper 2" (2003) starring Tom Berenger and Bokeem Woodbine. Edward Allen Harris (born November 28, 1950) is an American actor, producer, director, and screenwriter.  He is known for his performances in films such as "The Right Stuff" (1983), "The Abyss" (1989), "Glengarry Glen Ross" (1992), "Apollo 13" (1995), "Nixon" (1995), "The Rock" (1996), "Absolute Power" (1997), "A Beautiful Mind" (2001), "Enemy at the Gates" (2001), "Radio" (2003), "A History of Violence" (2005), "Gone Baby Gone" (2007), "The Way Back" (2010), "Man on a Ledge" (2012), "Gravity" (2013), "Snowpiercer" (2013), and "Run All Night" (2015).  Harris currently stars in the HBO sci-fi drama series "Westworld". Game Change is a 2012 American HBO political drama film based on events of the 2008 United States presidential election campaign of John McCain, directed by Jay Roach and written by Danny Strong, based on the 2010 book of the same name documenting the campaign by political journalists Mark Halperin and John Heilemann.  The film stars Julianne Moore, Woody Harrelson, and Ed Harris, and focuses on the chapters about the selection and performance of Governor of Alaska Sarah Palin (Moore) as running mate to Senator John McCain (Harris) in the Republican presidential campaign. Pollock is a 2000 biographical film which tells the life story of American painter Jackson Pollock.  It stars Ed Harris, Marcia Gay Harden, Jennifer Connelly, Robert Knott, Bud Cort, Molly Regan and Sada Thompson, and was directed by Harris. Enemy at the Gates is a 2001 French-American war film written and directed by Jean-Jacques Annaud and based on William Craig's 1973 nonfiction book "", which describes the events surrounding the Battle of Stalingrad in the winter of 1942 and 1943.  The film's main character is a fictionalized version of sniper Vasily Zaytsev, a Hero of the Soviet Union during World War II.  It includes a snipers' duel between Zaytsev and a "Wehrmacht" sniper school director, Major Erwin König. Stepmom is a 1998 comedy-drama film directed by Chris Columbus and starring Julia Roberts, Susan Sarandon, and Ed Harris.  Sarandon won the San Diego Film Critics Society Award for Best Actress and Harris won the National Board of Review Award for Best Supporting Actor, sharing the win with his role in "The Truman Show". Marian Harris is a Democratic politician who served in the Ohio House of Representatives.  A former educator and aide to United States Senator Howard Metzenbaum, Harris ran against Representative Larry L. Flowers in 2006 for a seat in the Ohio House of Representatives.  Although unsuccessful in her first attempt, Harris performed better than what was expected, coming very close to ousting Flowers.  As a result, she tried again for the seat two years later, in 2008.
Answer: Enemy at the Gates