Activate Skullport Merchant by paying {1}{U}, blinking it.
When Skullport Merchant enters, it and Deadeye Navigator's soulbond ability trigger twice.
Resolve both Deadeye Navigator triggers, repairing it and Skullport Merchant.
Resolve both Skullport Merchant triggers, creating two Treasure tokens.
Activate both Treasures by tapping and sacrificing them, adding {1}{U}.
Repeat.

Infinite artifact ETB

Infinite artifact LTB

Infinite artifact sacrifice triggers

Infinite creature LTB

Infinite creature ETB

Deadeye Navigator

Panharmonicon

Skullport Merchant

Activate Chthonian Nightmare by paying {E}{E}{E}, sacrificing Skullport Merchant and returning Chthonian Nightmare from the battlefield to your hand, returning Priest of Gix from your graveyard to the battlefield.
When Priest of Gix enters the battlefield, it triggers, adding {B}{B}{B}.
Cast Chthonian Nightmare by paying {1}{B}.
When Chthonian Nightmare enters the battlefield, it triggers, causing you to get {E}{E}{E}.
Activate Chthonian Nightmare by paying {E}{E}{E}, sacrificing Priest of Gix and returning Chthonian Nightmare from the battlefield to your hand, returning Skullport Merchant from your graveyard to the battlefield.
When Skullport Merchant enters, it triggers, creating a Treasure token.
Activate the Treasure by tapping and sacrificing it, adding {1}.
Cast Chthonian Nightmare by paying {1}{B}.
When Chthonian Nightmare enters the battlefield, it triggers, causing you to get {E}{E}{E}.
Repeat.

Infinite death triggers

Infinite creature sacrifice triggers

Infinite storm count

Chthonian Nightmare

Priest of Gix

Activate Ashnod's Altar by sacrificing Skullport Merchant, adding {C}{C}.
Skullport Merchant dies, triggering Nim Deathmantle, causing you to pay {4} to return Skullport Merchant from your graveyard to the battlefield, and attach Nim Deathmantle to it.
Skullport Merchant enters the battlefield, creating two Treasure tokens.
Activate two Treasure tokens by tapping and sacrificing those, adding two mana of any color.
Repeat.

Nim Deathmantle

Ashnod's Altar

Xorn

Activate Skullport Merchant by paying {1}{U}, blinking it.
When Skullport Merchant enters, it and Deadeye Navigator's soulbond ability trigger
Resolve the Deadeye Navigator trigger, repairing it and Skullport Merchant.
Resolve the Skullport Merchant trigger, creating two Treasure tokens.
Activate both Treasures by tapping and sacrificing them, adding {1}{U}.
Repeat.

Mondrak, Glory Dominus

Activate Emiel the Blessed by paying {1}, blinking Skullport Merchant.
When Skullport Merchant enters the battlefield, it triggers, creating a Treasure artifact token.
Activate the Treasure by tapping and sacrificing it, adding {1}.
Repeat.

Emiel the Blessed

Zirda, the Dawnwaker

Activate Emiel the Blessed by paying {3}, blinking Skullport Merchant.
When Skullport Merchant enters the battlefield, it triggers twice, and Preston trigger twice if it has power 2 or less, or once otherwise.
Resolve both Skullport Merchant triggers, creating two Treasure artifact tokens.
Resolve the first Preston trigger, creating a token copy of Skullport Merchant that is a 0/1 Illusion.
When the Skullport Merchant token enters the battlefield, it triggers twice, creating two Treasure tokens.
Repeat from step 4 for the remaining Preston trigger, if applicable.
Activate three Treasures by tapping and sacrificing them, adding {3}.
Repeat.

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