(Crossposting from Reddit to try to raise awareness)
Right... I just spent about 20 minutes going back and forth between difficulties double triple quadruple testing this, to really make sure I wasn't going insane. But the results are the same no matter how many times I've retried, so here goes: Has anyone else noticed that the same level and type of Act 2 mercs have different stats when hired from different difficulties, even though they aren't meant to any more? In case anyone else has been out of the patch notes loop like I was, and hadn't noticed the most recent mercenary changes in 2.4, here are the relevant points for you:
Updated each stat/skill gains in each difficulty to match so that there is no disadvantage of leveling up a Hell difficulty mercenary versus a Normal difficulty mercenary
and
Nightmare and Hell difficulty now have all 6 different aura types available from the Hire menu, instead of separating them out by 3 per difficulty. Normal is unchanged
As I'm typing this out, I'm realizing that they specifically said there's no disadvantage of leveling up a Hell vs Normal difficulty mercenary. What they perhaps kept the same as before, while equalizing the stats on the mercs from those two difficulties, are the stats on the mercenaries hired from Nightmare difficulty. So what the hell am I on about with this long wall of text? Here are some screenshots:
https://imgur.com/a/yjCaHAM
Attached are the stats on two naked lvl 64 Holy Freeze mercs, one hired from Nightmare difficulty, then brought over to Hell for ease of resistance demonstration, and the other hired from Hell difficulty. As a Holy Freeze merc doesn't exist in Normal difficulty as a hire option, and I frankly wasn't bothered grabbing 3 more screenshots of a BA/Prayer/Defiance merc, I didn't test the same in normal difficulty, but my guess is that the stats that merc would have would be the same as the stats on the Hell merc. Regardless, it is very clear that they have different stats across the board, and for me the worst part: some stats are better on the Nightmare difficulty hire, while others are better on the one from Hell. And this is only with the stats we're able to see in the game's UI. I certainly hope that hidden stats such as animation breakpoints aren't also different.
Is this (new) discrepancy commonly known? If so, what's the general concensus on which difficulty has the better merc in terms of stats across the board? If not, did I just discover a new part of the game that can be min-maxed? Why does this discrepancy exist at all? It seems very strange to me that they went with such a half-measure way of normalizing stats between difficulties, and kept an advantage for hiring from a certain difficulty in the game, despite having made an effort to eliminate a different one.
If this is also your first time reading about this issue, I would appreciate if you could hop into your game, with any character that is able to hire mercenaries from all 3 difficulties, and perform the same test as I have here, then leave your results as a comment, even if it's just a simple summary text of your findings, from the testing on one set of parameters.
I suspect that this stat discrepancy could exist as an issue across the board, for mercenaries of all levels, from all acts, and of all types, but there is not enough time in the day for me to test all those possible combinations by myself (and tbh I don't know why I'm writing this at 2 am on a Tuesday) If the issue exists on such a large scale, I think it is at least worth raising the player base's awareness on it, if not escalated as a bug report of some kind.