Look for an explicit play-alone statement
Read the publisher's description or rulebook for confirmation that no other game is required. Do not infer independence from box size, price or the amount of artwork. Some large expansions contain substantial material but still rely on basic cards, dice or boards from another box.
Check the standalone player count and included mode. A product may work alone for one count but combine with another box to support more players. Make sure the mode you actually want is included in the product you plan to buy.
Treat combining as a separate question
Find the rules for mixing products, including any restrictions on cards, characters or scenarios. Compatibility can be selective. Two boxes in the same series may share a core system while containing combinations that the publisher does not support.
Consider the practical effect of mixing. Extra content can enlarge setup choices and storage needs without changing the central activity. If you want a simple first game, play the standalone arrangement before building a combined collection. That also makes it easier to identify which rules belong to which box.
Verify the exact edition
Compare publication details and language with any existing game. Matching names alone are insufficient when a series has revised components. If hidden cards from different boxes have visibly different backs or sizes, check whether the combination was designed to accommodate that difference.
For a gift, the standalone feature reduces dependency risk but does not remove the need to consider taste, player count and reading demands. A product that runs by itself can still be a poor fit for the recipient's usual table.
