Observing your opponents' movements can give you important information about their tactics & hand placements. For example, if an opponent routinely removes particulaslots machines onliner cards from the discard pile, it can mean that they are trying to finish a particular set or sequence. You can use this information to make well-informed decisions about which cards to keep or discard. Also, you can learn a lot about your opponents' hand strength & confidence by watching how fast or slow they play their turns.
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