I'm trying to compile a list of all the Magic cards with quotes from real world literature. This is quite the task because no search parameter has a filter for this sort of nonsense. Making the task even more difficult is that not all versions of cads have the same flavor text. Fifth and Sixth edition Castle have one Macbeth quote while the Seventh edition has a different Macbeth quote, or how Fifth edition Energy Flux is the only version with a real world quotation. I have no problem pouring through Magic's backlog to find as many of these as I can however, one thing that would make this much simpler would be knowing which set is the cutoff for having these types of flavor text. So if anyone out there knows when WOTC quit using real world quotes that would be extremely helpful.
Edit: Just found out on another platform that the cutoff was in 2013. So, someone can lock this if needed.