Playing High Elves is a nightmare against Mazdamundi and Skarsnik. Their units are expensive and having 2 Ruination of Cities, 2 Banishments, or 3 mushroom caps delete expensive units until HE have nothing much left feels really unfair. A rampaging unit of dragon princes is most likely gone in one go. That's an ability that costs less than 200 gold deleting a 1400 unit. I think bound abilities this strong should have only 1 charge. They would still have ton of value and it wouldn't force single entity spam to survive all these bound vortexes. Ariel would be another example of having strong bound abilities that should be brought down to one charge.