Mikaeus, the Unhallowed + Goblin Bombardment + Safehold Elite

Mikaeus, the Unhallowed

Goblin Bombardment

Safehold Elite

How it works

1. Activate Goblin Bombardment by sacrificing Safehold Elite.
2. When Safehold Elite dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Resolve the Goblin Bombardment ability.
4. Activate Goblin Bombardment by sacrificing Safehold Elite.
5. When Safehold Elite dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
6. Resolve the Goblin Bombardment ability.
7. Repeat.