Why does opponent gain one new Lifelink Soldier card each turn?

I'm playing in an Event (Ravina At War - Eternity) and my opponent put a Lifelink Soldier card out. Much to my surprise, each time the opponent got a turn after that, another Lifelink Soldier card was automatically added to the existing ones. Why?

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Solution 1:

It turns out that the opponent's Haazda Marshal card creates lifelink soldiers when it attacks if the player has 2 or more creatures/creature reinforcements out.

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