A YouTuber’s self-financed and self-distributed sci-fi horror film is overturning industry expectations after it made it big at the box office over the weekend. “Iron Lung,” an indie video game adaptation from YouTuber Mark Fischbach (better known as Markiplier), pulled in $18.19 million at the domestic box office on opening weekend, according to final figures from Comscore. That’s more than six times its reported $3 million budget. The film, which Fischbach wrote and directed, played in 3,015