Artifact Creature with Mana Cost X and Toughness 0
Prerequisites
Artifact Creature with Mana Cost X and Toughness 0 in hand.
Thassa's Oracle in hand or in your graveyard or in your library.
All other permanents on the battlefield.
Sakashima the Impostor is a copy of Diligent Excavator.
({U} magic symbol) ({U} magic symbol) available.
Steps
Cast the artifact creature from your hand by paying ({0} magic symbol) .
Diligent Excavator and Sakashima the Impostor trigger, causing you to mill four cards.
The artifact creature enters the battlefield and dies as a state-based action due to having zero toughness.
Cast the artifact creature from your graveyard for its escape cost by paying ({0} magic symbol) and exiling any three cards from your graveyard, except Thassa's Oracle if it is in your graveyard.
Repeat from step 2 until you have an empty library.
If Thassa's Oracle is in your hand, cast it by paying ({U} magic symbol) ({U} magic symbol) .
Otherwise, cast Thassa's Oracle from your graveyard for its escape cost by paying ({U} magic symbol) ({U} magic symbol) and exiling three cards from your graveyard.
Thassa's Oracle enters the battlefield, causing you to win the game.