Probably everyone is sick when the opponent plays with magic. It used to be played with water and now with earth since the new set of cards started. Magic is hard to beat, especially if the opponent has one or even more cards that have the ability to heal tank.
By far the best team against magic is death.
This refers to the silver league that a lot of people play.
Below you can see one battle where the death team against the earth team (magic) did not lose a single point, not a single card.
The three cards that are most important are
Other cards are not so important.
So much for me so far, I think I've helped someone.
The following is a link to the battle where you can see the details.