While all-out aggression is certainly an option for the pair, they can also take things slower, leaning on Yidaros penchant for cycling to remove pesky artifacts and enchantments from the battlefield
Even with the errata to Brennen Blackcloud, cards like Light Bringer still create windows of opportunity too quickly and effectively to reasonably defend a Widows rush
As you can see, this is drawing one card per creature spell cast, typically for free, although the Lifecrafter's Bestiary costs mana
But, it is a Wolf, which could be relevant when Innistrad arrives in a couple months, and the enchantment does so much else that you can afford a less exciting creature
They start in the Command Zone and would change the way decks are built for the format