In the synopsis released by CW for "Supergirl" Season 2 in the episode "The Darkest Place", it was mentioned that "The Girl of Steel" will be facing Cyborg Superman. In the episode synopsis, Supergirl goes out in a rescue mission to save Mon-El, played by Chris Wood from the "Vampire Diaries" was kidnapped by CADMUS.
In the rescue mission in "Supergirl" Season 2, she will be encountering Cyborg Superman while saving Mon-El. Meanwhile James Olsen who is now known as the Guardian tries to clean up his name following accussations of murder which was done by different vigilante.
In the DC Comics Universe, according to Den of Geek, Hank Henshawk was Cyborg Superman's secret identity and is one of Superman's deadliest enemies. However in "Supergirl" Season 2, Hank Henshawk went in to a different direction instead being Cyborg Superman he is now the secret identity of J'onn J'onnz the Martian Man Hunter.
There were no actors revealed that will be playing Cyborg Superman. However the fans are hopeful that Tyler Hoechlin who plays the latest TV version of Superman will also play Cyborg Superman. His impression of Superman in "Supergirl" Season 2 was highly praised by fans.
There are also speculations that Jeremiah Danvers, Alex Danvers's father is a possible candidate to be Cyborg Superman in "Supergirl" Season 2, according to Bleeding Cool. It would also make sense why Jeremiah Danvers is a perfect fit as Cyborg Superman because he is played by Dean Cain who is a former Superman in "Lois and Clark: The New Adventures of Superman" film.
Aside from Cyborg Superman appearing to "Supergirl" Season 2, the "another vigilante" mentioned in the synopsis raised a lot of questions on who this vigilante is. At least everything will be answered when "The Darkest Place" will be airing on November 21 on CW.