As many of you may know by now, the post-credits scene for X-Men: Days of Future Past expectedly serves as a teaser for what, or rather who, is to come in the 2016 sequel, X-Men: Apocalypse. The stinger features a young gray-skinned En Sabah Nu, aka Apocalypse, who MTV News  reveals was played by an 18-year-old Brendan Pedder, with the supervillain's name being chanted as he's building blocks of a pyramid in Egypt. Speaking with Collider, screenwriter Simon Kinberg reveals that he and director Bryan Singer went through variations of the mid-credits scene before deciding on the one that we see. He also reassures that a new actor will play En Sabah Nu in X-Men: Apocalypse. Anyhow, watch the video interview above as Kinberg talks more about the post-credits scene's development. And check out MTV's Days of Future Past behind-the-scenes photo (below) featuring Bryan Singer and the aforementioned Brendan Pedder in costume.