Quick Legendary Lost Sector Farm. 50 second average to complete
Skydock doesn't require to kill any enemies to progress, making it perfect to run through undetected as a hunter.
I maxed out my mobility for a quick invis recharge.
I heard that the 4th horseman cat won't drop if you have several unfinished catalysts in your armory. So after running this for an hour (at 50 sec average runs) I went and completed 5 of my unfinished catalysts. Then I returned and got it on my 4th run. Could be coincidence.
Divinity is not required, but breaking his shield staggers him for a bit. You can also use shield disorient if you have it.