Summon: You may choose a card from your hand to swap with a or card in your Black Market.
Card sounds may differ from in-game as they get updated.
Ambush - An ambush unit can be played at the end of the enemy player's turn, or any time they are attacking you. If you played against a Killer or Relic Weapon attack, an Ambush unit will jump in the way to block that attack.
Summon - Does something when played
Market - Merchants allow you to store up to five cards in your Market when you build a deck. When cards are retrieved from a Market, they are drawn.