Maybe I did miss something?
Unfortunately, I do not remember the name of this big quest. I was told that - after fulfilling it - I will win the game. I had to open a gate and overpower this mighty hero on his dragon. (I hope you know, what I refer to?)
After some traveling from sub-quest to sub-quest, I finaly faced my destiny. The only way I could slay the mighty dragon was by weakening him with my beloved fellow heroes, leting them sacrifice themselves as a noble deed for the higher good. Then, I (the sovereign) could finally kill the foe.
And then... nothing! The game continued as if nothing happened at all. Only the monsters, that spamed when I opened the gate, rampaged through my poor kingdom.
Is this a bug? Or did I miss an important victory condition? Is it necessary to fight and kill the hero/dragon with the sovereign - and the sovereign only?
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Two minor bugs/issues, I didn't want to start a seperate thread for:
- A funny typo in the "Slavery"-Quest: The text sais something about a scene of "...morning, suffering and pain..." (or something similar). The point is: even I (as an obviously non-nativ speaker) had to lough about this. Please, fix it to "moaning". 
- Nothing serious, but still a little bit weird: the loading bar. It is nice to have one. But then, please let it represent the actual progress until game start. A bar is pointless, if it fills in a few seconds - and for at least an additional 30 seconds it stay at "full", until the game starts. But again: this is lowest priority possible and just something I recognized during my games.