Director Zack Snyder has tweeted the first photo of Jason Momoa as DC Comics superhero Aquaman from the set of Batman v Superman: Dawn of Justice, where the character will make his first appearance. Momoa's character will appear in future Justice League films as well as a proposed solo outing.
In the DC comic books, Aquaman is the king of the seven seas, hence the the words on the poster, "Unite The Seven". Momoa starred in the first two season of Game of Thrones and is also the star of the Sundance channel series The Red Road.
Batman v Superman: Dawn of Justice is an upcoming superhero film featuring the DC Comics characters Superman, Batman, Wonder Woman and Aquaman. It is the intended sequel to 2013's Man of Steel and the second installment in the DC Cinematic Universe.