Brandon Routh is set to reprise the role of Superman in this year's Arrowverse crossover. 1 / 7
There's just one minor issue: the Arrowverse already has a Superman, played by Tyler Hoechlin. 2 / 7
However, the multiverse means that the same character can be played by different actors. 3 / 7
For example, John Wesley Shipp is Earth-3's Jay Garrick, but he's also Earth-90's Barry Allen. 4 / 7
So Hoechlin's Superman can still be Clark Kent from Earth-38. 5 / 7
It can then introduce Routh's Superman from another Earth. 6 / 7
This works well for the Crisis on Infinite Earths storyline, which is all about the multiverse. 7 / 7