DC villain Prometheus, who was a primary villain of Arrow season 5, will make his DC-CW TV return in the upcoming crossover between Arrow, Flash, Supergirl, and Legends of Tomorrow, according to Entertainment Weekly.
However, there is a twist: this Prometheus is from Earth-X, the villainous alternate Earth at the heart of the TV crossover, which is appropriately titled "Crisis on Earth-X." Additionally, EW reports that this Prometheus will not be played by Josh Segarra, who portrayed him on Arrow. A different actor (though not necessarily an actor new to the show) is expected to take the role for "Crisis on Earth-X."
"Crisis on Earth-X" airs on CW over two nights, November 27 and 28.