An adversary may be concentrating on creating runs within a suit if, for instance, they routinely pick up cards from that suit while discarding others. With this information at your disposal, you can decide which rummy cercalcards to keep or discard for yourself. Also, anticipating the moves of your opponents can give you a big advantage when playing. You can tell an opponent is waiting for a certain card to finish their hand if you see them holding onto certain high-point cards without combining them into sets or runs. As you work to finish your own melds, you can strategically discard cards that could assist them by anticipating their needs.
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