One of my older unfinished fanfiction crossovers is a story combining Sliders and Xena: Warrior Princess. The Sliders slide into a San Francisco where everything looks like ancient Greek cities. The historical reason for this is because Alexander the Great did not die young. He continued across Asia, discovered the Pacific Ocean, found a way across, and set up a new Greek empire in North America.Caesar is more relatable.
Alex conquered the world as a 20-something.
Caesar cried about being a loser in comparison when he was in his 30s.
And since Xena and Gabrielle can turn up in any century the scriptwriter decides, I thought it would be fun to have a scene in which Professor Maximilian Arturo explains to Ares why it's impossible that he exists (since Arturo is all about science over religion and doesn't believe the Olympian gods were anything more than just fanciful stories).
Ares gets annoyed, and the Professor reaps the consequences... which were really fun to write. *snicker*