Blackwyrm quest bug?

[Syphiriah]

Hello.

So heres the thing... We just killed the blackwyrm to do the daily faction quest..... I got the achivement... but i didnt got the quest....

Pretty much just wasted 1 hour of my life to kill it.... for pretty much nothing..... :\

[Rakgi]

Same thing happened to me earlier. I was fighting it for quite a long time so i know i did enough damage yet i received nothing...

[GamerDLM]

You have to deal at least 1% damage on them in order for the chest to drop with the needed quest item.

 

Edit: I assume it's consecutive damage so I'm not sure if resurrecting or leaving combat resets it but you should be able to gauge how much damage you did based on the prestige points you get back if I understand it right.