Walking Ballista and Vraska, Swarm's Eminence Infinite Damage Combo

Step 1: Have Vraska, Swarm's Eminence on the battlefield.

Step 2: Cast Walking Ballista with at least 2 +1/+1 counters on it.

Step 3: Have Hardened Scales on the battlefield to increase the counters added.

Step 4: Use Animation Module whenever a +1/+1 counter is placed on Walking Ballista to create a Servo token and add an additional +1/+1 counter.

Step 5: Remove a +1/+1 counter from Walking Ballista to deal 1 damage to any target.

Step 6: Vraska, Swarm's Eminence triggers, adding a +1/+1 counter to Walking Ballista.

Step 7: Repeat steps 5 and 6 to deal infinite damage.