Adversaries Questions

Is there anywhere/anything that has been created that shows the link of rewards to adversaries? Similar to the info graphics showing which foundables you are likely to find in each challenge chamber? I understand the major fragments on each page (ex. defeat Draco Malfoy, get a fragment), but what about the extra ones that seem to appear randomly? Like the Nimbus 2001, for example, of Draco's page. Is there anything to identify how and when that fragment drops? Just trying to be strategic in playing adversaries in the future since the amount of SE and potions isn't worth the rewards if I've maxed out a particular fragment with green stars.