Activate Warren Soultrader by paying 1 life and sacrificing Forsaken Miner.
When Forsaken Miner dies, Sephiroth, Fabled SOLDIER // Sephiroth, One-Winged Angel triggers, targeting an opponent.
Forsaken Miner triggers, causing you to pay to return it from your graveyard to the battlefield.
Resolve the Sephiroth, Fabled SOLDIER // Sephiroth, One-Winged Angel ability, causing you to gain 1 life and causing an opponent to lose 1 life.
Resolve the Warren Soultrader ability, creating a Treasure token.
Activate the Treasure by tapping and sacrificing it, adding .
Repeat.
This loop is a masterclass in recycling, using Warren Soultrader to sacrifice Forsaken Miner for a Treasure token while simultaneously fueling the black mana needed to bring the Miner right back from the graveyard. Because Forsaken Miner's resurrection triggers whenever you commit a crime—which you effortlessly accomplish by having the dying Miner target an opponent with Sephiroth, Fabled SOLDIER // Sephiroth, One-Winged Angel—the cycle becomes entirely self-sustaining. Meanwhile, Sephiroth, Fabled SOLDIER // Sephiroth, One-Winged Angel watches the endless procession of sacrifices to drain your opponents' life totals down to zero.