At the beginning of your upkeep, create a 1/1 white and black Vampire creature token with lifelink and put a bloodline counter on Edgar Markov's Coffin. Then if there are three or more bloodline counters on it, remove those counters and transform it.
If a card that isn't a double-faced card is a copy of Edgar, Charmed Groom, it won't return to the battlefield when it dies.