If you want to make a splash in the Game of Thrones era, aim for the jugular and produce a nine-hour swords-and-dragons epic. That’s exactly what artistic director Nathan Allen did with his 2015 hit The Hammer Trinity. This year he dug even deeper with a live-action video game (The Last Defender) and a meticulous re-creation of an airline disaster (United Flight 232), cementing his theater’s reputation as not only a nerd haven but also one of the most ambitious companies in town.