“Real Steel” star Dakota Goyo has joined the cast of Scott Stewart’s thriller “Dark Skies,” which Jason Blum’s shingle Blumhouse Prods. is producing with Alliance Films.Dimension will distribute the Stewart-scripted pic, which follows an alien disguised as a human and a young boy who has been tagged for abduction. Josh Hamilton and Keri Russell star as the parents, while Goyo will play their eldest son. Goyo, who starred opposite Hugh Jackman in Shawn Levy’s “Real Steel,” recently joined the cast of Darren Aronofsky’s “Noah” as the younger version of Russell Crowe’s title character. Thesp will soon be heard as the voice of the young protag in DreamWorks Animation’s “Rise of the Guardians,” which hits theaters Nov. 21. He’s repped by WME and Thruline Entertainment.