Taking of the Necropolis [COMPLETE EDITION]

There's a different thing happening there. For example, if you take the first Dungeon located near the swamp, there will be fewer Gnolls there later, or you might simply lose some in battle. The point is that you need to reinforce your army with the third hero and take it reliably.

The strategy is undoubtedly good, but its weaknesses should have been pointed out from the start, and there wouldn't be any questions. Nub_hmm has a good video about the Dungeon near the swamp, but it doesn't show what will happen if the Vampires wait until the third round.