This loop is brilliantly orchestrated by Solemnity, which acts as a permanent shield against finality counters to completely bypass the restriction on Leonardo, Sewer Samurai's graveyard-casting ability. With that safety net in place, you can cast Ornithopter for zero mana directly from your graveyard over and over again, fueling Shilgengar, Sire of Famine's sacrifice outlet. Each time Shilgengar consumes the tiny flyer, it spins off a fresh Blood token, allowing you to feed the engine indefinitely for boundless triggers and artifact treasures.