Underworld Breach + Diligent Excavator + Thassa's Oracle + Sakashima the Impostor

Underworld Breach

Diligent Excavator

Thassa's Oracle

Sakashima the Impostor

How it works

1. Cast the artifact creature from your hand by paying 0.
2. Diligent Excavator and Sakashima the Impostor trigger, causing you to mill four cards.
3. The artifact creature enters the battlefield and dies as a state-based action due to having zero toughness.
4. Cast the artifact creature from your graveyard for its escape cost by paying 0 and exiling any three cards from your graveyard, except Thassa's Oracle if it is in your graveyard.
5. Repeat from step 2 until you have an empty library.
6. If Thassa's Oracle is in your hand, cast it by paying .
7. Otherwise, cast Thassa's Oracle from your graveyard for its escape cost by paying and exiling three cards from your graveyard.
8. Thassa's Oracle enters the battlefield, causing you to win the game.

This ingenious loop relies on Underworld Breach to let you repeatedly cast a zero-mana artifact creature from your graveyard by escaping it over and over, fueling its own escape cost by burning through the rest of your graveyard. Every time that artifact creature is cast, Diligent Excavator triggers to mill your library, while a clone created by Sakashima the Impostor doubles up those triggers to tear through your deck even faster. Once your library is completely empty, you can finally deploy Thassa's Oracle—either naturally or escaping it from your graveyard—allowing its enters-the-battlefield trigger to see zero cards remaining and instantly win you the game.