Sigilfall

Two lanesFights stay in their lane. The Undercity lane keeps new creatures Hidden until your next turn, so they can't be attacked.

FluxYou gain one more Flux each turn, up to 16. Whoever goes second gets a Boost Chip: +1 Flux for a turn, three times.

RecycleStuck with a card you can't use? Once per turn, tap it and Recycle it for 1 Flux: it goes to your Flatline and you draw a new card. Some cards also make you sacrifice cards from your hand for a payoff.

Reading cardsHold any card (right-click on a computer) to open it full size: every keyword, what it creates, and where a creature's stats came from. The strip at the top of the board shows recent plays; tap one to read it. While aiming an attack, targets show the damage each side will take.

SigilsYou start at 30 health (healing caps at 99) with sigils at 25, 20, 15, 10 and 5. Each sigil that breaks draws you a card.

Kindle and sigil triggersKindle: when the creature attacks, a random creature card in your hand gets +1/+1. Some Heliarch cards trigger each time one of your sigils breaks (every 5 health you lose).

OmensWhen a broken sigil draws an Omen card, you can play it free at once, even on your rival's turn.

GuardsYou can attack your rival's health directly unless they have a Guard in that lane. While a Guard is there, your creatures in that lane must attack it first.

SupportsEach player can keep four supports beside their health. They work every round. When all four are full, a new one makes you pick which to replace.

CopiesDecks hold 50 to 75 cards, up to 3 copies of a card. Unique Legendaries (creatures and programs) allow 1, unless they say Not Unique.

ClockA 5-card opening hand and 75 seconds per turn. When time runs out, your turn ends.