You know the flesh is weak and your towers stand on foundations of salt and sand when faced with sinners buffed with 1043094720243756354023 HP. Fret not though, in my unbridled ambition and infinite wisdom I shall bless thee with the limitless potential of ACTIVE abilities to punish sinners for eternity, or at least until you end your shift.
This will also help with the achievement Big Playa, which requires you to punish 20,000 sinners in a single run, not like the 200,000 and myself in my original run since I did not know how the scoring worked and thought 1 punished sinner = 1 point.
Since Grandma will be dying of old age with every extra draw, both Blood Clot and Blessing of Protection will provide the extra bit of survival we need and give a bit of synergy to cards that require shield. Similarly Struggle will give more CC and active abilities that deal damage will be helpful later since at any point in the game a purple Invigaron or Butcher of Sins is presented we will need them for the core of this build.
Building for damage and other tower aspects should be secondary to these things, but relevant enough to invest in at least a small amount. I specifically built for crit and a small amount of atk/projectile speed.
Butcher of Sins and the build
With the little cc from our setup, Butcher of Sins will consistently have enough time to wipe a map and effectively make your endless run, ‘endless’.