I've tried doing this quest 3 times now and everytime i become high enough light, get the quest, and get a fireteam ready to do it. It automatically finishes the patrol mission for me from cayde and I can't get the weapon, i've tried on all 3 character slots now and can't get it. Please help bungie.
There are several steps to completing the Rat King quest, in addition to the patrol. Each step requires at least one other fireteam member to either have the Rat King equipped or they need to also have the quest. Quite a few tutorials available online.