The original quest I've got has been Fire, but after failing to get anywhere with it I decided to ask for the new one hoping for the Water or at least the Life. No luck. Got the Earth.
Surprisingly, I had some luck playing with it and even though my Earth cards suck thanks to one of my enemies running away before the battles has started (twice) I finish it rather fast. The cards that I've got as a reward are nothing to speak about.