Cast Appa either from your hand or from the command zone by paying {W}{W} plus commander tax if applicable.
When Appa enters, it triggers, airbending Aang.
Cast Aang from exile by paying {0}.
Appa triggers, creating a 1/1 Ally creature token.
When Aang enters, it triggers, airbending Appa.
Cast Appa from exile by paying {0}.
Repeat from step 2.

Infinite LTB

Infinite ETB

Infinite storm count

Infinite creature tokens

Appa, Steadfast Guardian

Urza's Incubator

Aang, Airbending Master

Cast Aang by paying its mana cost.
When Aang enters, it triggers, airbending Appa.
Cast Appa from exile by paying {0} due to Doc Aurlock.
When Appa enters, it triggers, airbending Aang
Cast Aang from exile by paying {0} due to Doc Aurlock.
Repeat from step 2.

Doc Aurlock, Grizzled Genius

Aang, Swift Savior // Aang and La, Ocean's Fury

Cast Appa either from your hand or from the command zone by paying {W}{W} plus commander tax, if applicable.
When Appa enters, its first ability triggers, exiling Restoration Angel with the ability to cast it later from exile.
Cast Restoration Angel from exile by paying {0}.
Appa's second ability triggers, creating a 1/1 Ally creature token.
When Restoration Angel enters, it triggers, blinking Appa.
Repeat from step 2.

Restoration Angel

Semblance Anvil

Declare two creatures as attackers, ensuring to attack two different opponents. Commander Liara Portyr triggers, causing spells you cast from exile this turn to cost {2} less to cast.
Cast Appa by paying its mana cost.
When Appa enters, it triggers, exiling Restoration Angel with the ability to cast it from exile later.
Cast Restoration Angel from exile by paying {0} due to Commander Liara Portyr.
When Restoration Angel enters, it triggers, blinking Appa
Repeat from step 3.

Infinite blinking of nonland permanents you control

Commander Liara Portyr

Cast Appa either from your hand or from the command zone by paying {2}{W}{W} plus commander tax, if applicable.
When Appa enters, its first ability triggers, exiling Restoration Angel with the ability to cast it later from exile.
Cast Restoration Angel from exile by paying {1} and tapping Appa.
Appa's second ability triggers, creating a 1/1 Ally creature token.
When Restoration Angel enters, it triggers, blinking Appa.
When Appa enters, its first ability triggers, exiling Restoration Angel with the ability to cast it later from exile.
Cast Restoration Angel from exile by paying {0} and tapping Appa and the Ally token.
Repeat from step 4.

Infinite tapped creature tokens

Dazzling Theater // Prop Room

Cast Appa by paying {2}{W}{W}.
When Appa enters, its first ability triggers, exiling Restoration Angel with the ability to cast it later from exile.
Cast Restoration Angel from exile by paying {0} and tapping Appa and another creature you control.
Appa's second ability triggers, creating a 1/1 Ally creature token.
When Restoration Angel enters, it triggers, blinking Appa.
Repeat from step 2.

Hoarding Broodlord

Cast Appa by paying {2}{W}{W}
When Appa enters, its first ability triggers, exiling Restoration Angel with the ability to cast it later from exile.
Cast Restoration Angel from exile by paying {0}.
When Restoration Angel enters, it triggers, blinking Appa.
Repeat from step 2.

Sage of the Beyond

Cast Appa by paying {4}.
When Appa enters, its first ability triggers.
Holding priority, activate Chromatic Orrery by tapping it, adding {C}{C}{C}{C}{C}.
Resolve the Appa trigger, exiling Chromatic Orrery with the ability to cast it later from exile.
Cast Chromatic Orrery from exile by paying {2}.
Displacer Kitten and Appa trigger.
Resolve the Appa trigger, creating a 1/1 Ally creature token.
Resolve the Displacer Kitten trigger, blinking Appa.
When Appa enters, its first ability triggers, exiling another nonland permanent with the ability to cast it later from exile.
Cast the permanent from exile by paying {2}.
Displacer Kitten and Appa's second ability trigger.
Resolve the Appa trigger, creating a 1/1 Ally creature token.
Resolve the Displacer Kitten trigger, blinking Appa.
Repeat from step 2.

Infinite colored mana

Infinite colorless mana

Infinite card draw

Infinite draw triggers

Displacer Kitten

Chromatic Orrery

Cast Eternal Scourge from exile by paying {3}.
Appa's second ability triggers, creating a 1/1 Ally creature token.
Activate Ashnod's Altar twice by sacrificing Eternal Scourge and the Ally, adding {C}{C}{C}{C}.
When Eternal Scourge dies, Mimic Vat triggers, exiling Eternal Scourge from your graveyard.
Repeat.

Infinite sacrifice triggers

Infinite death triggers

Eternal Scourge

Ashnod's Altar

Mimic Vat

Cast Appa by paying {2}{W}{W}.
When Appa enters, it triggers, airbending Rasputin and Wispweaver Angel.
Cast Rasputin from exile by paying {2}.
Appa's second ability triggers, creating a 1/1 Ally creature token.
Activate Rasputin's first ability seven times by removing seven dream counters from it, adding seven {C}.
Cast Wispweaver Angel from exile by paying {2}.
Appa's second ability triggers, creating a 1/1 Ally creature token.
When Wispweaver Angel enters, it triggers, blinking Appa.
Repeat from step 2.

Combos with "Appa, Steadfast Guardian"