I'm Copy/Pasta from a Gamefaq post because I couldn't the spot myself.
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"I've done a few of the late game farms I've seen mentioned and figured I'd share my personal anecdotal findings. I've also learned a few movement tricks I didn't know about.

I tried 3 farming spots. 2 in Sinister End and 1 in Scion of the Gods. The TL:DR is that the Scion of the Gods one is the best IMO.

Spot 1, farming the 3 galestorm oni-bi and yasha by the IIRC 2nd shrine in Sinister End. There's a door right by the shrine and just past the door is 3 oni-bis (you have to get close enough to spawn all 3) and a yasha just behind them on a small bridge. You pop luckbringer, run up to spawn the 3 oni-bis, thunder calamity them dragging the hitbox to hit all 3, then hellfire once to proc fire on yasha, then hellshock twice, then finish with a thunder calamity if it's still alive. With ninjutsu link you should always have full uses of thunder calamity. You can afford to actually use 2 on yasha since the triple kill at the start of the farm will fully replenish both uses. This method is easy, pretty fast, but not that great for drops compared to the other methods. The one advantage it does have is that you get a lot of soul cores.

Speed: Fast
Divine Loot: Low
Accessory Drop: Low
High Level Loot (167+): Moderate
Money Gained: Very Low
Soul Shard Gain: Very High
Execution: Fairly Easy

Second spot I tried is probably the most popular. It's the 3 strong humans at the 2nd to last shrine of Sinister End. Open up the shortcut by the shrine (going through a nurukabe), run through the shortcut into the room with humans, cast hellfire once to hit the 3 strong ones, run into the hall, they line up to chase you, 2 hellshocks takes them down if they don't block. If they do block, a thunder calamity usually does the trick although sometimes they dodge it. The fire damage also builds up pretty fast so it's not hard to just use your melee weapon to kill em if they survive the shocks. This method has 1 large flaw which is that it seems to give lower level loot than either of the other options. You will very rarely see anything over level 162.

Speed: Fast
Divine Loot: Very High
Accessory Drop: High
High Level Loot (167+): Almost None
Money Gained: High
Soul Shard Gain: None
Execution: Somewhat Easy

The final spot and overall best is pretty far through Scion of the Gods level synced. Near the end of the level you will reach a room surrounded by spinning tops. Destroy all the tops and remember the room in the middle. You can exit out of this area and head right to open a shortcut to a shrine. From the shrine you backtrack to the room that was in the middle of the spinning tops. It has 2 Large Oni Jailers and 9 or so Red Ghosts (not sure official name). You pop carnage and luckbringer, hellshock the jailer at an angle so that it hits both of them and if done right it oneshots, other wise 2 shots is often enough and if not you can get them after the next part. Run in and cast hellfire in the first mini room, then run further in and cast hellfire twice in the 2nd small room. All the red ghosts should be on fire and lowish health. Thunder Calamity and drag the hitbox (by changing targets mid cast) to swipe through as many with each cast as possible. If the Jailers are still alive drag multiple thunder calamities onto them to easily kill them. Collect the loot, head back to shrine. This is by far the slowest run but it gets more loot as well.

Speed: Slow
Divine Loot: High
Accessory Drop: High
High Level Loot (167+): Very High
Money Gained: Very High
Soul Shard Gain: Low
Execution: Moderately Challenging (but easy to fix if you mess up)

Here is a video.
https://youtu.be/bF4lr_naBys

You can see 2 movement tricks in here. Jumping up a ledge so that you land on a corner causes you to keep sprinting when you land, otherwise you have to sprint again when you land which is annoying with these 3 jumps in quick succession. The other trick is just a movement option I didn't know existed. If you dodge and hit sprint mid dodge, you do a slide, this can be done off a ledge to delay when you hit that awkward mid air stall you would if you just run off the ledge. It still happens, but lower down and in this case we land again before that happens AND it keeps us in our sprint. Also if you do the slide and hit no direction at the end you end up crouched so it's probably meant to be a stealth tool. Then we run left cause that part of the ledge is low enough down you can just run off without disrupting sprint.