Each turn players will be given 3 Spell Cards, open hand, to choose from. Both players then have 30 seconds to look at their opponent's cards and compare them with their own. Based on that information, players will each choose a card to play, face down, then both cards are revealed simultaneously.
What players choose is very important, as some elements have to ability to cancel other, for example, a Water spell will cancel out a Fire spell. And if both players play the same element, all the cards effects are doubled. Successfully predicting what your opponent will play each turn is crucial to winning.