Dawnfeather Eagle — ruling 1

The set of creatures affected by Dawnfeather Eagle’s triggered ability is determined as the ability resolves. Creatures you begin to control later in the turn and permanents you control that become creatures later in the turn won’t get +1/+1 or gain vigilance.

Dawnfeather Eagle — ruling 2

Dawnfeather Eagle’s triggered ability affects itself.

Dawnfeather Eagle : règles, fonctionnement et interactions (MTG)

Dawnfeather Eagle is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Flying When this creature enters, creatures you control get +1/+1 and gain vigilance until end of turn.

How it works : Dawnfeather Eagle

Original English text — Wizards of the Coast / Scryfall

#1February 9, 2017· Wizards of the Coast
The set of creatures affected by Dawnfeather Eagle’s triggered ability is determined as the ability resolves. Creatures you begin to control later in the turn and permanents you control that become creatures later in the turn won’t get +1/+1 or gain vigilance.
No other card is named in this ruling.
#2February 9, 2017· Wizards of the Coast
Dawnfeather Eagle’s triggered ability affects itself.
No other card is named in this ruling.