At the beginning of your first main phase, you may pay B. If you do, transform Eirdu.
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Isilu, Carrier of Twilight
Flying, lifelink
Each other nontoken creature you control has persist.
At the beginning of your first main phase, you may pay W. If you do, transform Isilu.
Reverse Type:
Legendary Creature — Elemental God
Flying, lifelink
Each other nontoken creature you control has persist. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)
At the beginning of your first main phase, you may pay W. If you do, transform Isilu.