RPGMemes

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A) this makes no sense to describe as railroading, apparently finding anything plot or backstory related is railroading?

B & C) Players not doing what a dm expects isn't railroading. If the dm then turned around and said "no you don't do that" or decides to make it impervious to prestidigitation, that might fit the definition.

Railroading is removing player agency and not giving players choices. Players just doing something unexpected that throws you for a loop? That's called DMing.