Anti-Venom, Horrifying Healer + Agatha's Soul Cauldron + Lae'zel, Vlaakith's Champion + Walking Ballista

Anti-Venom, Horrifying Healer

Agatha's Soul Cauldron

Lae'zel, Vlaakith's Champion

Walking Ballista

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 Lae'zel.
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 vicious loop centers around Agatha's Soul Cauldron, which allows you to exile Walking Ballista and grant its activated abilities to any creature you control with a +1/+1 counter on it. With Lae'zel, Vlaakith's Champion amplifying counter placement, any damage dealt to Anti-Venom, Horrifying Healer instead gets prevented and translates into a surplus of +1/+1 counters. By leveraging the Cauldron-granted abilities, Anti-Venom can continuously ping any target by removing a counter, and then replenish and grow those counters to deal infinite damage and secure the win.