During their Upkeep Phase, players ready their Cores so that they are available during their opponent’s turn. This means that a player will always have all their Cores available to play Reactions against their opponent’s Actions. It is important to note that any exhausted Cores will not be available on the player’s next turn, so they won’t be able to play cards of that colour.

They then discard any cards that remain in their hand, and draw a new hand of 5 cards.