Sorry, I didn't announce this clearly at update time and I should have.
Yes, the Lore & Legend body drops were deliberately modified to offer the quests. This change accompanied a couple behind-the-scenes upgrades to how the mastery quest drop tables and random updates actually work, and it all got sort of blended into a vague line in the GU 53 patch notes.
Now, you can start a Lore & Legend quest while you're actually out in the field killing the monsters you need for updates, in addition to getting it from the books should you happen to find them. I know this change doesn't make any sense from a lore perspective, but then again, examining boarfiend spleens to learn more about their weaknesses never made much sense in the first place
This decision was motivated by a desire to make the quests smoother and more coherent from a gameplay perspective, especially for new players encountering these quests for the first time. They're not ridiculously easy now -- the average is still more than 100 kills to completion -- but you are no longer completely at the mercy of the random number generator and third party websites to get and complete your creature masteries.
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