It can be difficult to know which card to counter, but I generally ask myself, Based on the information given, what card is the bridge to their end-game?, and counter that spell
Speaking of elements, earthbending is a mechanic from Avatar: The Last Airbender that is all about animating lands and giving them recursion, so I'll leave them to their own article, though they very much deserve mention here
If youre willing to wait until your fifth turn to have found the needed legendary creatures and are happy with a 75% chance of having Kolvori be a 6/6, then you only need a mere thirteen non-Kolvori legendary creatures, which is a much easier number to come to and still sounds acceptable to me
You can also exchange Crystals for additional coins in the shop, though Crystals are much harder to collect so you might want to avoid doing this
Remember Abzan Company