How does building work in the card game casino?

In the card game Casino, building is a strategic move used to capture cards from the table. When you build, you play a card from your hand onto the table to create a specific numerical combination that you intend to capture on a subsequent turn.1

To perform a build, you must hold the card required to capture it in your hand. There are two primary ways to build:

• Single Rank: You add a card from your hand to a card of the same rank on the table (e.g., adding a 3 to a 3) and announce "Building 3s." This build can only be captured by another 3.1
• Numerical Combination: You combine a card from your hand with one or more cards on the table to form a new total (e.g., playing a 3 onto a 3 to announce "Building 6"). This build can only be captured by a 6.1

Builds can be extended by opponents if they hold the necessary card to increase the total, provided the build was not a single-rank announcement. However, if an opponent captures your build before your next turn, you lose the opportunity to claim those cards.1