Kodama of the East Tree | Archelos, Lagoon Mystic | Petrified Field

(and two other cards)

Play
Petrified Field.
When
Petrified Field enters the battlefield,
Kodama of the East Tree and
Retreat to Emeria trigger.
Resolve the
Kodama of the East Tree trigger, putting nothing onto the battlefield.
Holding priority, activate
Petrified Field's second ability by tapping and sacrificing it, returning
Echoing Deeps from your graveyard to your hand.
Resolve the
Retreat to Emeria trigger, creating a 1/1 Kor Ally creature token.
When the creature token enters the battlefield,
Kodama of the East Tree triggers, putting
Echoing Deeps from your hand onto the battlefield untapped due to
Archelos as a copy of
Petrified Field.
When
Echoing Deeps enters the battlefield,
Retreat to Emeria triggers.
Holding priority, activate
Echoing Deeps using
Petrified Field's second ability by tapping and sacrificing it, returning
Petrified Field from your graveyard to your hand.
Resolve the
Retreat to Emeria trigger, creating a 1/1 Kor Ally creature token.
When the creature token enters the battlefield,
Kodama of the East Tree triggers, putting
Petrified Field from your hand onto the battlefield.
When
Petrified Field enters the battlefield,
Retreat to Emeria triggers.
Repeat from step 4.