Activate Sakashima of a Thousand Faces using Avatar Kuruk's ability by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
At the beginning of your end step, Airbender Ascension triggers, blinking Sakashima of a Thousand Faces. Choose to have it enter the battlefield as a copy of Avatar Kuruk.
Repeat each turn.

Infinite turns

Lock

The Legend of Kuruk // Avatar Kuruk

Airbender Ascension

Sakashima of a Thousand Faces

Activate Avatar Kuruk by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
At the beginning of your end step, Airbender Ascension triggers, blinking Avatar Kuruk and causing it to return to the battlefield as The Legend of Kuruk with two lore counters on it due to Doubling Season.
The Legend of Kuruk's first and second chapter abilities trigger, causing you to scry 2, draw a card, scry 2 and draw another card.
Move to your next turn. At the beginning of your precombat main phase. The Legend of Kuruk triggers, putting two lore counters on it. Its third chapter ability triggers, causing you to exile it and return it to the battlefield as Avatar Kuruk.
Repeat.

Doubling Season

Activate Avatar Kuruk by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
Repeat each turn.

Elvish Refueler

Activate Avatar Kuruk by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
Deal combat damage to an opponent using Brago. Brago triggers, blinking Avatar Kuruk and causing it to return to the battlefield as The Legend of Kuruk. Choose to have it enter with three lore counters due to its read-ahead ability given to it by Barbara Wright.
The Legend of Kuruk's third chapter ability triggers, causing you to exile it and return it to the battlefield as Avatar Kuruk.
Repeat each turn.

Barbara Wright

Brago, King Eternal

Activate Quicksilver Elemental by paying {U}, causing it to gain Avatar Kuruk's activated abilities until end of turn.
Activate Quicksilver Elemental using Avatar Kuruk's ability by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
Repeat each turn.

Quicksilver Elemental

Activate Avatar Kuruk by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
At the beginning of your end step, Y'shtola Rhul triggers, blinking Avatar Kuruk and causing it to return to the battlefield as The Legend of Kuruk with a lore counter on it.
The Legend of Kuruk's first chapter ability triggers, causing you to scry 2 and draw a card.
Move to your next turn. At the beginning of your precombat main phase. The Legend of Kuruk triggers, putting a lore counter on it. Its second chapter ability then triggers, causing you to scry 2 and draw a card.
Activate Lulu by paying {3}{U}, causing you to proliferate and put a lore counter on The Legend of Kuruk.
The Legend of Kuruk's third chapter ability triggers, causing you to exile it and return it to the battlefield as Avatar Kuruk.
Repeat.

Lulu, Stern Guardian

Y'shtola Rhul

Activate Marvin using Avatar Kuruk's ability by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
Activate Marvin by paying {1}{U}, blinking it.
When Marvin enters, Deadeye Navigator triggers, repairing it and Marvin.
Repeat each turn.

Marvin, Murderous Mimic

Deadeye Navigator

Activate either Progenitor Mimic or Avatar Kuruk by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
Move to your next turn. At the beginning of your upkeep, Progenitor Mimic triggers, creating a token copy of Avatar Kuruk.
Repeat using the Avatar Kuruk token.

Progenitor Mimic

Activate Volrath by paying {1}, causing it to become a copy of Avatar Kuruk until your next turn.
Activate Volrath by paying {20} minus {1} for each creature and/or artifact you can tap while activating it, causing you to take an extra turn after this one.
Repeat each turn.

Search Results