It was once said that Plan B is unplayable without Mushin No Shin. Surely that was written before Matrix Analyzer hit the meta. Oh wait, that was core set...

Advancing Plan B during a run makes for a lot of fun. Puppet Master allows you to bump it once just before access. Three Matrix Analyzers on a Plan B, and you can score a 3-point agenda outright, if the runner doesn't chicken out. Watch as your piddling plan appreciates right before your eyes from something unplayable into something score-worthy. No credits needed to fire.

As others have said, Plan B is also quite useful in combination with Shell Corporation and Back Channels. All in all, this card is incredibly fun.

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The problem with both Matrix Analyzer and Puppet Master is what you stated "if the runner doesn't chicken out." Most of the time if the runner sees you advancing a face-down card that they know they can reach, they're probably not going to access it unless they think it's a trick. —