You may buy one or more of the face up Power Cards. Each card has a cost in Energy shown in the top left corner of the card. When a Power Card is bought, it is immediately replaced with a new card from the deck. The new cards are immediately available for purchase.
You may spend two (2) Energy to sweep all the three face up cards and deal three new cards to replace them. These new cards are immediately available for purchase.
As long as you have Energy , you can continue to buy or sweep cards.
All cards are either Keep Cards with an on-going effect, or Discard Cards with an immediate effect.