The Earth Crystal

If one of the creatures is an illegal target and the other one isn't as The Earth Crystal's last ability tries to resolve, the original distribution of counters applies and the counter that would have been put on the illegal target is lost. It won't be put on the remaining legal target instead.

If the rare case where you control two of The Earth Crystal, the number of +1/+1 counters put on a creature is four times the original number. Three of The Earth Crystal multiplies the original number by eight, and so on.

To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as a flashback cost), add any cost increases (such as kicker costs), then apply any cost reductions (such as that of The Earth Crystal's first ability). The mana value of the spell is determined by only its mana cost, no matter what the total cost to cast that spell was.