Saga of dice discussing the very earliest 4e event results.
Too early to draw too many conclusions, the faction packs are new, in many cases people maybe haven't figured out what's good yet, or if they have they don't have the new hotness painted yet, etc. But there are some clear early themes:
manifestations, ~especially~ morbid conjurations, seem op, and dramatically increase the value of access to good wizards, including multicasters, casting bonuses, and casters that can be included in other heroes' battalions. Who would have thought that free, infinitely re-summonable units would be strong? But yeah, these don't cost points, so I have no idea how they'll balance them. Accross the board nerfs to the warscrolls? Limit multicast wizards and priests to only summoning one per turn? Limit armies as a whole to only summoning one per turn? Limit each individual manifestation to only be summoned once per game? Probably nothing that drastic, at least in a first pass, but /some/ kind of nerf is likely on the way.
Cavalry in general seems too strong relative to infantry. Cavalry units across the board got a lot better in 4e - many of them gaining an extra wound and damage on the charge. Some units even have control 2, making them as efficient as equivalent infantry units at objective control. Almost all cavalry units are more durable point for point, fight at least as hard on the charge, and are twice as fast or faster, with the new rules strongly rewarding speed and maneuverability. I'm not sure what the fix will look like here. They could just mess with points values - increasing cavalry or decreasing infantry accross the board. Or they might actually edit warscrolls, reducing dropping some of the extra wounds they handed out in the faction packs. I wouldn't be at all surprised to see outlier cav units like hexwraiths with control 2 reduced to control 1 so that infantry have at least ~some~ area of expertise where cavalry aren't just inherently superior.
Finally, and I know none of us here want to hear this, Nighthaunt is too strong. Yes its still early days and people are still figuring out other factions where as the ABCs of nighthaunt are obvious at first glance which is certainly giving them a head start that other factions will gain ground on as their players work them out, but even so the faction is too strong. In 2e and 3e they were shackled, so to speak, by 1 inch combat ranges on 32mm bases for their best units and in 3e especially ethereal was more of a hindrance than a help due to how common save stacking was, and how much both the devs and players in general leaned on mortal wounds to get around it. The new nighthaunt rules and points saw the faction overall get a big boost to compensate for their previously poor performance at the same time as the core rule interactions holding them back were all removed like Rock Lee dropping his training weights.
The result is, in early figures at least, a near 70% win rate. That's just too much to attribute to people not knowing how to play against them yet.
Which in turn has people talking about early nerfs. There are already rumors of an early balance patch - probably in august, and it's probably going to hit Nighthaunt pretty hard. Especially since the problem with the faction isn't just one or two units, it's basically everything apart from maybe chainrasps & glaivewraiths. So near accross the board points hikes would not be surprising.
In terms of actual rules errata, I also wouldn't be surprised to see a nerf to the Death Stalkers battle formation. Run & Charge AND Retreat & Charge isn't just more than any other nighthaunt battle formation does, it's more than pretty much any other battle formation in the game does. Even in a faction that can already charge in combat, that's still doing twice as much it probably should be doing, and I wouldn't be at all surprised to see it erratad to being just one or the other bonus instead of both at the same time.
So those are the changes I would suggest bracing for if you're looking at playing nighthaunt in 4e, +20ish points to most of your units and half of death stalkers getting chopped off. Maybe an additional hit to hexwraiths and harrows as part of a general nerf to cavalry. And if that's all we see then we didn't exactly dodge a bullet, but at least it maybe didn't hit any vital organs.
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As for the other undead factions...
Soulblight Gravelords are also running a bit high, though that may just be their strong ability to take advantage of manifestations (via multicasters and vyrkos sub-hero casters) and access to multiple good cavalry units, and if we see general nerfs to cavalry and manifestations then GW might not see a need to hit the faction any harder, as they're not necessarily running so high that you couldn't attribute it to people still gettitng used to the new system. Dire wolves might see a bit of a points hike - yes as beasts they don't have quite all the same bonuses that cavalry are enjoying, but they are fast
chaff in a ruleset that favors being fast, and they're especially competent at limiting the maneuverability of your opponents units & blocking off huge sections of the board. I think regular skeleton warriors are kind of bad right now, but they probably aren't bad enough in and of themselves within a faction that's doing pretty well overall for the devs to notice & do anything about them this soon.
OBR are currently sitting pretty at almost exactly 50% with their above average warscrolls and faction rules held in check by generally high points values.
OBR might arguably have some internal balance issues in terms of immortis vs. stalkers or morteks vs. kavalos or the like, but other than kavalos maybe getting caught in a general nerf to cavalry I don't think there's anything so eggregious that the devs would need to intervene this early.
In contrast to the other undead factions, FEC are running a bit low early on. But that probably is attributable to people still getting a hang of the rules and the faction. FEC are in general the most fragile of the undead armies, without OBR's strong saves, NH's ethereal, or SG's mix of cheap expendible
chaff and high durability elites. As a result FEC punishes players harder than other undead factions for making the sorts of mistakes that are inevitable when adjusting to a new ruleset. They do have access to a lot of recursion, at least in theory, but FEC players have to jump through a fair few hurdles to activate it and it comes at the cost of feeding frenzy, so there's a lot of player skill required to optimize the process of gaining and spending noble deed points, balancing abhorrants vs. courtiers in list constrction, etc. So yeah, I think FEC as a faction are maybe just taking a bit longer for players to wrap their heads around than OBR, Soulblight, or (especially) Nighthaunt.
That said, FEC also don't take as much advantage of the generally op stuff in 4e as other undead do. They have casters for manifestations, but they aren't quite as efficient in terms of number of casts or casting bonuses, and the fact that they need courtiers for recursion means you probably can't just span casters only for your heroes. FEC also don't really have any regular cavalry, just the morbhegs. Which are good, but 'monstrous' cavarly units aren't really the problem that 'normal' cavalry are. In particular they lack the control score needed to /also/ challenge infantry on contesting objectives, plus they're 3 wounds less than a typical cavalry unit, so they actually have ~some~ weaknesses. If the cavalry and caster nails get hammered down then FEC are likely to see a slight boost out of it, at least relatively speaking, even without any buffs to FEC specifically.
