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

by the way, I initially had the idea to create a knight-crusader for the fourth or fifth level – this idea loses out to the ballista, but I now have a new thought – an orc warrior from the free cities.
The ballista doesn't actually look that great; questions arise regarding the machine handling skill, as well as regeneration and repair...
The orc can be based on the chieftain, on a 4-cell unit, with upgrades dressed in armor like Maximus, and given good weaponry.