Activate Goblin Bombardment by sacrificing Fiend Hunter.
When Fiend Hunter dies, its second ability triggers, returning Hero of the Dunes to the battlefield from exile.
When Hero of the Dunes enters the battlefield, it triggers, returning Fiend Hunter from your graveyard to the battlefield.
When Fiend Hunter enters the battlefield, its first ability triggers, exiling Hero of the Dunes.
Resolve the Goblin Bombardment ability from step 1, dealing 1 damage to any target.
Repeat.
This clever loop relies on a recursive dance between Fiend Hunter and Hero of the Dunes, seamlessly recycling them through the graveyard with the help of Goblin Bombardment. When you sacrifice Fiend Hunter to Goblin Bombardment, it triggers its own exit ability to return Hero of the Dunes, which in turn brings Fiend Hunter right back from the graveyard and immediately exiles Hero of the Dunes again. This creates a perpetual engine that fuels infinite damage and infinite triggers, all while the passive power boost from Hero of the Dunes quietly oversees your tiny, looping army.