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.
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.
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pulsemeat
