Boss Drop Rate

I actually disagree about passive skills hitting the boss affecting drop rate.

Looking at Magnus specifically -- without any interference I can get all 5 capes/shoes 100% with just my drop gear and no card or event.
I've had Xenon's loot for me, with their middles doing some damage (<0.1% hp) and still get all the drops. However, I've had Terebii; (paladin) loot before where he would attack. I was on a 2x card at the time, as well as all my gear (gear includes wolf), and only got 2 shoes and 3 capes. I believe there is a threshold damage that needs to be dealt for that individual to be included in the drop rate calculation.

This method of party drop rates has been around for as long as I can remember. Back when I killed Empress for weapons (when no one else in the server could), I noticed more drops when we both bought 2x cards.

Interesting. I didn't ever boss with a Xenon so I don't know if they are an exception or if it just works differently. Do you know if the Xenon skill triggers aggro? As I recall the Xenon Missile skills don't trigger aggro so that might explain why it doesn't consider those attacks worthy of making a player an active attacker, whereas I'm pretty sure both the I/L Chilling Step and Kanna's Ether Pulse trigger aggro. Familiars would also not cause a player to be considered an active attacker if this is the case because those don't cause aggro either, same with most final attack skills (but you'd need to attack at least once for the FA to trigger anyway at most bosses).