Mercy Graves and Otis will be joining the cast.
Mercy will be played by Rohna Mitra (The Last Ship) and has been described as "“stepping out of the Luthor shadow and running her own show." “With her biting wit and lethal brawn, Mercy steadily becomes a key figure in National City’s growing ‘human-first’ movement.”
Otis will be played by Robert Baker (Grey's Anatomy), and will be Mercy's brother and enforcer who "while he may not be the smartest person out there, he’s definitely one of the deadliest — especially when it comes to dealing with aliens."