I also tested it on a Hero. It is completely passable. There will be a set of undead artifacts, daily automatic recruitment of troops, and it can be completed normally. The only thing is that it would be good to develop leadership so that all recruited companions turn into undead. In the center of the dungeon, there are free black knights, and since the map is linear, no one will appear from anywhere, so develop and complete the task. You won't be allowed to the second location until you clear the first one.