RTF is a global modification that replaces all towns in the game.

Cerberus was only in hell according to Dante's version.

yes, Dante's Divine Comedy is considered a very authoritative work because it's not a modern creation, but a medieval text written by a priest.

Added 4 minutes later
well, as for unicorns, there are several options, and I don't remember why we started discussing them anymore. :D

I think that in a medieval setting, we should either use classic unicorns, or none at all, or create a separate Greek biome with a Greek faction.