Sylvan vs. Necropolis

What do you mean by saying you would put everyone in their place? I don't quite understand you. You can have a maximum of 4 sworn enemies (for example, if you have an amulet of mastery)...
I agree that there are artifacts that reduce stats, including luck, but don't forget that a hero's luck and the luck of units are not always the same...

Is Chaos better than Haven against Necropolis? I doubt it...