Kremlin is a new Slavic city.

Instead of cats, you could add characters like the Nightingale robber, werewolf, bog creature, or leshy. They appear in folklore, so why not? A bogatyr could be a sorcerer, and they could be given some kind of ancient Russian magic or something similar.

Added 2 minutes ago


Added 10 minutes ago
I apologize, I didn't look closely enough at the heroes and missed the presence of sorcerers as heroes.