Which version of Necropolis do you like best?

I didn't play part 1. Part 2 is well-made and balanced. Part 3 is average (it seems well-thought-out, but there are few differences in gameplay). Part 4 is a complete disaster (the biggest disgrace of part 4 and the entire series).
Part 5 is quite well-thought-out (finally, they added the undead symbol – Death with a scythe!!! – and the appearance of the buildings is quite good, although I don't really like the zombies). I didn't play part 6 as the undead faction.