What legendary item to farm first?

Hey all I’m 11 days in to the game albeit the first week or so I wasn’t really playing too much. I’m at floor 510 and I have the special top hat as well as spider necklace. I was farming for the plunger hat bc I saw its one of the best legendary items. Should I just be farming Quasar for it with training keys and bogar? Or is there another item I should be farming for instead?