Cast Aethertide Whale by paying eight {E} if able or {4}{U}{U} otherwise.
When Aethertide Whale enters the battlefield, it triggers twice, causing you to get twelve {E}.
Activate Aethertide Whale by paying {E}{E}{E}{E}, returning it from the battlefield to your hand.
Repeat.

Infinite creature LTB

Infinite creature ETB

Infinite storm count

Aethertide Whale

Nissa, Worldsoul Speaker

Panharmonicon

Cast Aethertide Whale by paying eight {E} if able or {4}{U}{U} otherwise.
When Aethertide Whale enters the battlefield, it triggers, causing you to get twelve {E}.
Activate Aethertide Whale by paying {E}{E}{E}{E}, returning it from the battlefield to your hand.
Repeat.

Aether Refinery

At the beginning of your combat phase, Saheeli triggers, causing you to pay {E}{E}{E} to create a token copy of Aethertide Whale with haste.
When the Aethertide Whale token enters the battlefield, it triggers, causing you to get twelve {E}.
Declare Lightning Runner as an attacker, triggering its ability, causing you to get {E}{E}{E}{E} and then pay eight {E} to untap all creatures you control and to get an additional combat phase after this one.
Repeat each combat phase.

Infinite creature sacrifice triggers

Infinite death triggers

Infinite combat phases

Infinite creature tokens with haste

Infinite untap of creatures you control

Infinite mana creatures you control can produce

Infinite energy counters

Saheeli, Radiant Creator

Lightning Runner

At the beginning of your combat phase, Saheeli triggers, causing you to pay {E}{E}{E} to create two token copies of Aethertide Whale with haste.
When the Aethertide Whale tokens enter the battlefield, they trigger, causing you to get twelve {E}.
Declare Lightning Runner as an attacker, triggering its ability, causing you to get {E}{E} and then pay eight {E} to untap all creatures you control and to get an additional combat phase after this one.
Repeat each combat phase.

Adrix and Nev, Twincasters

Cast Petals of Insight by discarding Aethertide Whale.
Conspiracy Theorist triggers, exiling Aethertide Whale and allowing you to cast it from exile this turn.
Resolve Petals of Insight, putting the top three cards of your library on the bottom of your library, and returning Petals of Insight to your hand.
Cast Aethertide Whale from exile by discarding Petals of Insight.
Conspiracy Theorist triggers, exiling Petals of Insight and allowing you to cast it from exile this turn.
Aethertide Whale enters the battlefield, causing you to get six {E}.
Activate Aethertide Whale by paying {E}{E}{E}{E}, returning it to your hand from the battlefield.
Cast Petals of Insight from exile by discarding Aethertide Whale.
Repeat from step 2.

Combos with "Aethertide Whale"