Dominion Saboteur + Mikaeus, the Unhallowed + Goblin Bombardment

Dominion Saboteur

Mikaeus, the Unhallowed

Goblin Bombardment

How it works

1. Activate Goblin Bombardment by sacrificing Dominion Saboteur.
2. When Dominion Saboteur dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it. As it enters, choose to have it copy a non-Human you control with a -1/-1 counter on it, and then also enter with a -1/-1 counter on it.
3. Resolve the Goblin Bombardment ability
4. Repeat.