Making her Six Flags theme park debut, a life-like animatronic of the DC Super-Villain, Harley Quinn, sprays laughing gas on riders at Six Flags Magic Mountain&rsquo;s new JUSTICE LEAGUE: Battle for Metropolis attraction. Riders are members of the JUSTICE LEAGUE Reserve Team to save the City of Metropolis with climactic interactive battle scenes between the DC Super Heroes and Super-Villains. (Photo: Business Wire)