How does reserving a card work in Splendor?
Take a face-up card, or the top card of any deck without showing it, into your hand, and take 1 gold if any is left. You can hold 3 reserved cards at most, you can't discard them, and the only way to get one out of your hand is to buy it.
The rule:
In Splendor, reserving takes your action: take a face-up card or the secret top card of a deck, plus 1 gold if any remain. You can hold 3 reserved cards at most, and the only way to clear one is to buy it.
Reserving is your action for the turn. The end-of-turn checks (10-piece limit, nobles) still happen. To reserve:
- Pick a card: any face-up card, or the top card of one of the three decks, kept secret from the others.
- Take 1 gold, if there’s any left. If the gold is gone, you can still reserve.
- Refill: if you took a face-up card, replace it from the same deck, unless that deck has run out.
Limits:
- 3 reserved cards in hand at most. A full hand of 3 rules out this action.
- Reserved cards can’t be discarded. You get rid of one only by buying it.
- Reserved cards still in your hand at the end don’t cost you anything.
Example:
Mia reserves a face-up level 2 card a rival needs and takes 1 gold. The card is replaced from its deck. It's Mia's third reserved card, so she can't reserve again until she buys one.
Why players argue about it:
Players argue about reserving when no gold is left (you still can), about discarding reserved cards (you can't) and about whether leftover reserved cards cost points at the end (they don't).