The CW is casting up on its DC superhero series. First up, Nick Zano has joined "Legends of Tomorrow" as Dr. Nate Heywood, a character in the comics who was the grandson of Justice Society of America hero Commander Steel and eventually becomes Citizen Steel. Zano will specifically be playing Heywood the doctor. Meawhile Rick Gonzalez has been cast as the vigilante Wild Dog who will join Team Arrow on the network's "Arrow".