If someone hands you a deck, you can be sure there are 52 cards covering four suits.
The universe is finite. The cards are the cards, and games work precisely for that reason. Every deck is the same, and all the players have the same options.
Some of the systems we compete in have a limited number of cards, known to all.
More often, though, there is the possibility of surprise. Options that weren’t considered by others, paths that are still unexplored. Technology mints new cards, but so do brave decisions and commitment.
It’s rare to know all the available cards, and rarer still to have them all.