The idea is relatively simple:
-Players start with 40 Health at base.
-When building your deck, you may put in up to 2 Duels Passives, 1 Duels Hero Treasure (the ones you get at the start of a run), and 2 Duels Treasures. You may also choose a Hero Power based on your class.
-Each passive, hero treasure, hero power, and regular treasure has certain deckbuilding requirements. For example, Shadowcasting 101 might require that “No minion in the deck can cost more than (3)”, Oops! All Spells! might require that “No minions can be put in the deck”, and Ironweave Bloodletter might require 3 Blood Runes. Since everyone has the ability to put these passives into their deck, and they aren’t considered cards- well, you know what they say about what happens when everyone’s Super.