Vigor + Corpsejack Menace + Walking Ballista

Vigor

Corpsejack Menace

Walking Ballista

How it works

1. Activate Walking Ballista by removing a +1/+1 counter on it, targeting itself, but putting two +1/+1 counters on it due to Vigor.
2. Activate Walking Ballista by removing a +1/+1 counter on it, dealing 1 damage to any target.
3. Repeat.

This elegant loop turns Walking Ballista into a self-sustaining engine by weaponizing its own damage against itself. When Walking Ballista pings itself for 1 damage, Vigor steps in to prevent that harm and instead grants a +1/+1 counter, which Corpsejack Menace brilliantly doubles into a net gain of two counters. Because you put more counters on than you remove to pay the cost, you can endlessly repeat the process to generate infinite +1/+1 counters for your board while spraying infinite damage across any targets you choose.