What is the best race in Heroes of might and magic 5?

i like the necropolis race mostly because of their resurrcting powers and how powerful the creatures can be... I'm playing tribes of the east version 1.0 and that i once got 2k of skelton archers and I'm stuck on the conquest weich is in campigan 2, mission three and can somebody please tell me how to beat it because I'm stuck on it.