When Stonework Puma enters, Haru triggers, targeting Stonework Puma as it is a land due to Toph.
Activate Goblin Bombardment by sacrificing Stonework Puma.
When Stonework Puma dies, Haru triggers, returning Stonework Puma from your graveyard to the battlefield tapped.
When Stonework Puma enters, Haru triggers, targeting Stonework Puma as it is a land due to Toph.
Resolve the Goblin Bombardment ability.
Repeat from step 3.
This ingenious loop transforms ordinary artifact creatures into a perpetual engine of destruction by leaning heavily on Toph, the First Metalbender's static ability to treat your nontoken artifacts as lands. Because Stonework Puma enters the battlefield as both an artifact and an Ally, its arrival triggers Haru, Hidden Talent to earthbend it into a creature-land hybrid. This clever classification allows you to feed Stonework Puma directly into Goblin Bombardment, sacrificing it for damage and instantly triggering its own return to the battlefield thanks to the earthbend safety net.