Crisis On Infinite Earths: 36 Easter Eggs, Cameos And References You Probably Missed
34. Crisis On Earth-X
The next dimension to meet its demise was Earth-X, as we caught a brief glimpse of Russel Tovey's Ray Terrill/The Ray just before the dead earth was engulfed by a wave of antimatter.
A direct Arrowverse reference this was ironically one of the more unexpected cameos, but it was a neat little nod to previous crossover Crisis On Earth-X.