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

The Barbarians don't befriend anyone (maybe a little with the Free Cities), and as for our old friends... the question is, is Gotai still alive!

I think it's like this: Kujin could have communicated with spirits and understood that the world will soon end, and with Gotai, she will gather all the orcs and head towards Stonehelm.
The Dark Elves will decide that the orcs want to destroy their race forever, and the elves will attack.
After Sareta teleports from Stonehelm, he decides to create his own army by subjugating the orcs with the power of chaos; the orcs mutate, driving the elves into cities.
Only the Ice King will stop the orcs by freezing the lands of the elves; then he will go north to the elves' native lands, give the city of Shagui to the elves, capture the ancient elven cities, crush the local dragon knight fortresses, unite with the mountain nagas, and reach the sea where he will meet the elven and dwarven pirates.
The orcs will remain only in the heart of the dragon gate, in the Sahara desert, and on the islands of Pao.