Cast Oathsworn Vampire either from your hand or graveyard by paying 1.
Edgar triggers, creating a 1/1 Vampire creature token.
When the Vampire and Oathsworn Vampire enter, Soul Warden triggers twice, causing you to gain 2 life.
Activate Warren Soultrader twice by paying 2 life and sacrificing Oathsworn Vampire and the Vampire token, creating two Treasure tokens.
Activate two Treasures by tapping and sacrificing them, adding 1.
Repeat.
This loop is a masterclass in recursive sacrifice, turning a single Vampire into a self-sustaining engine. It all begins when you cast Oathsworn Vampire, whose ability to return from the graveyard is unlocked the moment Soul Warden rewards you with life for its arrival. Soul Warden also watches the extra body generated by Edgar Markov's eminence ability, ensuring you gain enough life to keep the cycle going. Meanwhile, Warren Soultrader devours those creatures to fuel the mana needed to recast Oathsworn Vampire over and over again, converting a steady stream of life and fangs into infinite sacrifice and lifegain triggers.