You can learn a lot about their tactics and possible hands by watching these behaviors. For instance, an opponent may be nearing the completion of a meld if they routinely dranew rummy 51w cards from the discard pile instead of the deck. You can also use this information to make better decisions about your own gameplay by keeping track of which cards have been discarded. It could be a good idea to modify your strategy and concentrate on lower-point combinations if you observe that some high-value cards have already been discarded.
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