When Faceless Butcher enters, its first ability triggers, exiling Sister Hospitaller.
Activate Woe Strider by sacrificing Faceless Butcher.
When Faceless Butcher dies, its second ability triggers, returning Sister Hospitaller from exile to the battlefield.
When Sister Hospitaller enters, it triggers, returning Faceless Butcher from your graveyard to the battlefield.
When Faceless Butcher enters, its first ability triggers, exiling Sister Hospitaller.
Resolve the Woe Strider ability.
Repeat from step 3.
This clever loop sets up an endless cycle of sacrifice and resurrection by cycling Faceless Butcher and Sister Hospitaller back and forth between the battlefield, graveyard, and exile. Woe Strider acts as the crucial sacrifice outlet that triggers the Butcher's departure, while its passive scry ability and token creation help grease the wheels. Every iteration uses Sister Hospitaller's entry trigger to fish the Butcher right back out of the graveyard, simultaneously padding your life total with the creature's mana value.