Element Synergy!

Play 2 cards of the same element in one turn and the element pays a bonus: Fire deals damage, Ice grants Block, Shadow applies Weak, Holy heals, Void draws a card. Every further card of that element this turn triggers the bonus again.

Play 2 cards of the same element in one turn to trigger its bonus. Every later card of that element in the same turn triggers it again.

Numbers from the current game data