The Hero's Path

Hello, thank you very much for the map. I've never played anything like it before; everything is done very well! There are many quests, interesting neutral creatures, and a day/night cycle. It's great! The only problem is with the quest to destroy the wyvern raids and the descent from the mountain. Could you please tell me how to get down from the mountain after the battle with the demons at the top? I've replayed it twice, and both times I got stuck there; I can't get down. A catapult can't be placed there to fly down. And the spell that the mage in the dungeon promised to cast doesn't work...