As I understand it, there are two main build paths for Dwarves due to their specific characteristics: focusing on "light" and "chaos" magic. In the latest expansion, a build focused on "summoning" looks good, but what is the better choice overall? With decent mana, it's good to sit back and bombard the opponent with "meteor shower," "fireball," or something similar. However, with large armies, I think it's more convenient to play with "light" magic; the buffs will provide a greater positive effect – Dwarves will become tougher, faster, and stronger, and the opponent can try to reduce magic damage in various ways, such as using "ice shield," but it's unlikely they can block light magic.
I haven't played as Dwarves much; I'm just starting – I've played against them in 3 games and won twice, so I'm looking for advice.