Tactics for Necropolis.

I usually focus my Champion of the Realm on the strongest enemy and then attack groups of Liches to get a good splash damage. I use Vampires to take out the enemies I dislike the most, unless they are mechanical units. The main thing is to observe the battle and adapt accordingly.

This is usually a standard approach against AI opponents, but human players will likely find a weakness in this tactic. I think everyone has played like this at some point, right?
P.S. This is not meant as criticism, it's just a tactic that works well against AI but might be more challenging against a human player.