These are the rules for the playtest that Phrancis and Jay did:
Each player starts with a deck of 52 cards. The cards range in strength from 1 to 13, and there are four of each strength in the deck.
Before the game begins, each player draws a hand of 5 cards. The rest of their cards are placed to the side and comprise their Draw deck. Once destroyed, scrapped, or used, cards are placed in a pile next to the draw deck called the Discard pile.
Starting with a randomly chosen player, play alternates back and forth between the players. The player may play as many cards as they can afford to play during their turn.
Each card has a cost in either Mana or Scrap. Each turn, the players Mana Total increases by 1, starting with 1 on the first turn. Mana is returned to the current Mana Total at the start of each turn. Unused mana is lost at the end of a turn.
To gain scrap, a player takes a card that is currently in their field and places it in their discard pile. Scrap only depletes when it is used, and is only accumulated when cards are scrapped.
The goal of the game is reduce the other players health to zero. Each player starts with 10 health. Damage is caused to the other player by attacking them directly with units or by spillover damage. (spells are not currently in the game yet)
Each player has a Field in front of them which contains all of the units that they have played. When a unit is played, it has the Sickness on that turn and may not attack until the next turn. A player may choose to attack with any unit that does not have the sickness. There is no limit to the number of units that a player may have on the field.
When a player attacks, if the opposing player has any units in their field, the attacking player must direct their attack against one of those units. If they have no units in their field, the opposing player may be attacked directly. If attacking a unit, the Strength of the attacking unit is compared against the Health of the defending unit. If it is greater, the defending unit is destroyed, and any extra damage carries over against that player as Spillover Damage. The Strength of the defending unit is also compared against the Health of the attacking unit, and if it is greater, the attacking unit is destroyed.
(the rules for spells/buffs are not in here yet but they are in the game)