Azorius Herald
{2}{W}
Creature — Spirit
Oracle Text
This creature can't be blocked.
When this creature enters, you gain 4 life.
When this creature enters, sacrifice it unless {U} was spent to cast it.
Watch Out
ETB trigger, not a cast triggerRules Note
This card's ability triggers when it enters the battlefield, not when it's cast. Effects that double ETB triggers (like Panharmonicon) work here. Countering the spell prevents the creature from entering, so the ETB won't fire.