When Stalactite Dagger enters, it triggers, creating a 1/1 Shapeshifter creature token with changeling.
When the Shapeshifter enters, Haru triggers, earthbending Stalactite Dagger, as it's a land due to Toph.
Activate Woe Strider by sacrificing Stalactite Dagger.
When Stalactite Dagger dies, Haru triggers, returning Stalactite Dagger from your graveyard to the battlefield.
Repeat steps 2 and 3 once.
Resolve the Woe Strider ability.
Repeat from step 4.
This clever loop transforms a humble piece of equipment into a versatile engine by bridging the gap between card types. Toph, the First Metalbender turns your nontoken artifacts into lands, allowing Haru, Hidden Talent to target Stalactite Dagger with its earthbend ability whenever a changeling token enters the battlefield. You then feed that animated equipment directly to Woe Strider's sacrifice ability; because Toph's earthbend grants a safety net that returns the land to the battlefield tapped when it dies, Haru triggers again to loop the Dagger endlessly back into play, generating infinite sacrifices, scrys, and token triggers.