The Viking leaders offer a distinct advantage in that they can pick up and drop troops off as they move and can perform something akin to an overrun if they can whack all the defending locals in one round of combat. I forget which Viking leader begins the game, but Dennis gets one to start and draws others from a deck of cards each turn.
For me, one outstanding aspect of this design is the way its author has modeled two rather different armies fighting over a large expanse of city. This was, of course, something John Hill sought to do in his Stalingrad design from 1980 – units from two forces that have much the same sort of information on them, but behave differently once they start moving and fighting on the game map. In a very deft way, I believe Adam Niechwiej has bedded both forces into the battle environment, creating a distinct character for each of them in a relatively brief set of rules. In play, the experience of commanding either the Soviets or the Germans will feel very different, and for reasons beyond the Soviets having this or that number of units or the Germans simply (one might erroneously assume) being outnumbered.