Cast Oathsworn Vampire either from your hand or graveyard by paying 1.
Edgar triggers, creating a 1/1 Vampire creature token.
Activate Warren Soultrader by paying 1 life and sacrificing Oathsworn Vampire.
When Oathsworn Vampire dies, Blood Artist triggers, causing target opponent to lose 1 life and you to gain 1 life.
Resolve the Warren Soultrader ability, creating a Treasure token.
Repeat steps 3 through 5 once, sacrificing the Vampire token instead.
Activate two Treasures by tapping and sacrificing them, adding 1.
Repeat.
This elegant loop turns the endless marching of the Undead into a fatal drain on your opponents, powered entirely by a self-sustaining cycle of life and death. Warren Soultrader acts as the engine, turning your creatures into mana and Treasures while feeding the lifegain requirement for Oathsworn Vampire to crawl right back out of your graveyard. Meanwhile, Blood Artist watches the procession, turning every sacrifice and subsequent re-entry into an absolute hemorrhage of life totals for the table. Best of all, Edgar Markov fuels the entire operation from the command zone or battlefield, passively churning out extra Vampire tokens with his Eminence ability every time you cast a Vampire so you always have the fodder needed to keep the machinery turning.