A Diablo 4 player has run the numbers to determine that the best way to grind some of the game's best loot is to run either a pretty low-tier Nightmare Dungeon, or the absolute hardest ones in the game - and not to bother with anything else.
In a post on the game's subreddit, user fpsthirty said that once they "got bored of aimlessly grinding to lvl100," they decided to turn their efforts to something more useful: "to record the item power of each looted item with the subsequent grouping by level of Nightmare Dungeon." The aim was to determine whether there was a significant relationship between item power and dungeon level, and their findings may be sobering for hardcore grinders.
To gather their data, they spent 18 days running 400 dungeons (five of each tier between 21 and 100), collecting and recording 8,104 Ancestral items in total. They say regret set in around tier 30, but they were determined to see the idea through to its completion.
What follows is a wall of data that I've struggled to parse, but a handy TL;DR provides a good place to start. It suggests that anywhere between Tier 40 and Tier 90, all Ancestral gear drops with pretty much identical power - 70% of drops varied by just three points. That still rings pretty true from Tier 91-100 (though the gear is very slightly more powerful), but you'll also have higher odds of getting an Ancestral drop - around 60% more at Tier 100 than at Tier 40.
As summarised by another user, "you get more Ancestral rares in higher tiers, they're just not really much better per drop quality-wise. So if you want a chance to get an 820 weapon and don't care how good the chance is, you can just run [Tier] 40s." However, if you want to get as many Ancestrals as possible per run,
Read more on gamesradar.com