Smaug the Impenetrable + Metalwork Colossus + Blasting Station + Xorn

Smaug the Impenetrable

Metalwork Colossus

Blasting Station

Xorn

How it works

1. Activate Blasting Station by tapping it and sacrificing Metalwork Colossus, dealing 1 damage to Smaug.
2. Smaug triggers, creating two artifact tokens due to Xorn.
3. Activate Metalwork Colossus by sacrificing the two artifact tokens, returning Metalwork Colossus from your graveyard to your hand.
4. Cast Metalwork Colossus by paying 0.
5. When Metalwork Colossus enters, Blasting Station triggers, untapping Blasting Station.
6. Repeat.

This loop transforms a dragon's hoard into lethal artillery by putting Smaug the Impenetrable right in the line of fire. When Blasting Station pings Smaug for 1 damage, Smaug the Impenetrable triggers to generate a Treasure token, which Xorn graciously multiplies into two shiny treasures instead of one. Those very same tokens are then fed directly into Metalwork Colossus's second ability, allowing the giant automaton to leap from your graveyard straight back to your hand. From there, you cast Metalwork Colossus for free—thanks to its mana-reducing cost being heavily subsidized by the artifacts you already control—triggering Blasting Station to untap itself so the whole cycle can begin anew.