Suggestions by @schemestr

Grant Gustin

as The Flash in Casting James Gunn's DCU! :D

Boyd Holbrook

as John Constantine in Casting James Gunn's DCU! :D

Penn Badgley

as The Question in Casting James Gunn's DCU! :D

Grace Caroline Currey

as Zatanna in Casting James Gunn's DCU! :D

Ron Pearlman

as Kilowag in Casting James Gunn's DCU! :D

Pablo Schreiber

as Ares in Casting James Gunn's DCU! :D

Marko Zaror

as Bane in Casting James Gunn's DCU! :D

Dan Stevens

as The Joker in Casting James Gunn's DCU! :D

Tom Brittney

as Batman in Casting James Gunn's DCU! :D

Zoey Deutch

as Harley Quinn in Casting James Gunn's DCU! :D

Josh Brolin

as Thomas Wayne in Casting James Gunn's DCU! :D

Thomas Haden Church

as Commissoner Gordon in Casting James Gunn's DCU! :D

Corey Mylchreest

as Cyclops in All the X-Men Characters