Anti-Venom, Horrifying Healer + Agatha's Soul Cauldron + Walking Ballista + Caradora, Heart of Alacria

Anti-Venom, Horrifying Healer

Agatha's Soul Cauldron

Walking Ballista

Caradora, Heart of Alacria

How it works

1. Activate Anti-Venom using Walking Ballista's ability by removing a +1/+1 counter from it, targeting itself and putting two +1/+1 counters on it due to its replacement effect and Caradora.
2. Activate Anti-Venom using Walking Ballista's ability by removing a +1/+1 counter from it, dealing 1 damage to any target.
3. Repeat.

This lethal loop begins by using Agatha's Soul Cauldron to exile Walking Ballista, granting its activated abilities to any creature you control that bears a +1/+1 counter. Caradora, Heart of Alacria ensures that any counters placed on your creatures are amplified by an extra one, while Anti-Venom, Horrifying Healer uses its own damage-prevention static ability to transform any self-inflicted pings into an influx of growth. By activating Walking Ballista's counter-removal ability to ping Anti-Venom, you trigger its replacement effect to prevent the damage and accumulate a surplus of +1/+1 counters—more than enough to fuel an infinite cycle of damage to any target.