There's a very good reason Edgar Markov is one of the most heavily played Magic: The Gathering Commanders, and you'll soon find that out for yourself when building a deck around the Vampire lord
Keep your energy going by including typical white draw engines, like Tocasias Welcome, Mentor of the Meek, and Caretakers Talent, and aim to build a big board before your opponents can respond
Sideboard-wise, Survival is capable of packing in a few more silver bullet style cards (usually in the form of cards like Containment Priest to shut down Dredge strategies) as well as hate cards for Shops/Outcome in the forms of additional Manglehorn and even Energy Flux or Kataki, War's Wage
Even in the face of instant speed answers like a Shock it is quite easy to deploy the Ophiomancer when the opponent is tapped out so as to ensure at least one snake is made and value is gained
When the gatewatch vanquished Griselbrand, Avacyn was released
You tell me to go pound sand, and you go play Hearthstone instead