Crisis On Infinite Earths: 36 Easter Eggs, Cameos And References You Probably Missed
3. Marv Wolfman
Marv Wolfman is considered comic book royalty for writing the original Crisis On Infinite Earths, so it was only fitting that he co-wrote the Arrow episode with Marc Guggenheim. What we didn't expect, however, was for the legend to show up on-screen in the concluding part.
Appearing in the Legends of Tomorrow entry, he was the fan who informed Supergirl and The Flash that they had been teaming up with Green Arrow, the Legends and Batwoman 'since forever'.
A subtle cameo that significantly progressed the plot, Marv was a real hero here.