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

Good idea, by the way :) but how would an adept use the casting animation?

We'll have to use a standard mage from the Academy instead of an adept; the effect isn't tied to bones, so there shouldn't be any problems.

Added after 9 hours and 13 minutes

The first volley fire setup in the world has a large area of effect, but it fires arrows, and it works by attaching rockets to the arrows. We could create something similar; if that doesn't work, we can go back to a ballista with explosive projectiles.