Mikaeus, the Unhallowed + Goblin Bombardment + Pith Driller

Mikaeus, the Unhallowed

Goblin Bombardment

Pith Driller

How it works

1. Activate Goblin Bombardment by sacrifiicing Pith Driller.
2. When Pith Driller dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
3. When Pith Driller enters the battlefield, it triggers, putting a -1/-1 counter on it.
4. Resolve the Goblin Bombardment ability, dealing 1 damage to any target
5. Repeat.

This loop revolves around Mikaeus, the Unhallowed, whose static anthem gives all your non-Human creatures undying, ensuring they return to the battlefield after perishing if they lacked a +1/+1 counter. By feeding Pith Driller into Goblin Bombardment, you turn every iteration of damage into a fresh sacrifice while sending the Driller to the graveyard to trigger its own revival. When Pith Driller returns, its enter-the-battlefield ability places a -1/-1 counter on itself, which instantly neutralizes the +1/+1 counter granted by undying through state-based actions. This brilliant cancellation clears the slate for the next recursion, letting you endlessly repeat the sacrifice and reload cycle to deal infinite damage.