Special Guest Stars Elizabeth Tulloch as Lois Lane Elizabeth Tulloch as Lois Lane (Earth-75) Melissa Benoist as Kara Danvers / Supergirl Caity Lotz as Sara Lance / White Canary Stephen Amell as Oliver Queen / Green Arrow Tom Welling as Clark Kent of Earth-167 Jon Cryer as Lex Luthor Tyler Hoechlin as Clark Kent / Superman Dominic Purcell as Mick Rory / Heat Wave of Earth-74 Brandon Routh as Ray Palmer / The Atom Brandon Routh as Clark Kent / Superman of Earth-96 Katherine McNamara as Mia Smoak Matt Ryan as John Constantine Grant Gustin as Barry Allen / The Flash Candice Patton as Iris West-Allen Guest Stars Erica Durance as Lois Lane of Earth-167 Wentworth Miller voices Leonard A.I. Audrey Marie Anderson as Lyla Michaels / Harbinger Johnathon Schaech as Jonah Hex of Earth-18 Kevin Conroy as Bruce Wayne / Batman of Earth-99 Co Starring Elias Hogewoning as Baby Jonathan Kent Benjamin Hogewoning as Baby Jonathan Kent