Nighthaunt - The discorporate change is actually a nerf, in that it has to be used in the hero phase, not in reaction to being attacked. So if you discorporate one unit the opponent can just concentrate their damage on other units. It's still good, but much less effective than reactive use, especially since armies tend to focus their damage in particular phases - mostly shooting or mostly combat - rather than spreading damage out over multiple phases.
I'm not complaining, mind. Nighthaunt have been heavily overperforming for all of 4e, they needed some major nerfs, but imo the problem is how their design concept - ethereal saves, everything fast and flying, no ability to even lock them in combat since they can charge out at other targets - interact with the fundamental core rules of 4e. There's also the heavy redundancy in their units. Revenants gone up a ton of points? Hardly matters. Just run harridans or reapers instead, they're all basically the same unit.
I just don't think there's a points cost where this army with these core rules works. They'll either be overpowered or unfieldable. But maybe I'm wrong! I'm often wrong about balance issues. And the discorporate change shows that GW is willing to make changes to their faction rules, not just their points cost. Take away their ability to charge out of combat with one thing into something else - ie, if they're in combat with something before the charge they still have to be in combat the same unit after - and I think they might be close to ok. Beyond that they still really need to diversify the function of the units - maybe make reapers slower, maybe lower harridans save, etc. But that kind of thing will likely need to wait for a battletome update at least.
anyway as is the changes we see here are fair, and might lower their win rate some, but I still think they'll at least be among the strongest armies in the game, if not still outright the strongest. Well see, though. Again, I'm often wrong about these things.
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OBR - it seems that the Devs were specifically targeting 30 Kavalos + either Katakros or, especially, Nagash builds. The 30 kav + nagash build in particular is no longer fieldable due to being 2100 points for just that. However, Nagash + 2x10 kavalos + 2x teratics is 2k points on the nose and pretty close to what the 30 kav build did, so not even that build is really dead.
There was a nice quality of life change for the harvester - it now gains tithe points from any model in an enemy unit that dies if the unit is in combat range of the harvester, not just if that specific model is in combat range, plus it saw a price discount. Unfortunately, I still don't think it hits hard enough to justify even the reduced price just in itself, and even with the qol fix it doesn't offer enough support to morteks to make them viable to build around. Maybe if OBR could use the new field marshal honor guard, but they don't have any infantry subcommanders to put it on. As is I just don't think morteks work well enough to justify building around to begin with, even with kavalos going up in points, especially with the anti-synergies of not benefiting from the anti-charge relentless discipline and their shield wall shutting off katakros's buff. We'll see, though.
OBR have been hanging out around the upper end of 'acceptable' win rates, mostly off of Kavalos but more recently we have seen some crawler builds gaining traction. The +20 points per 5 kav might bring their win rate down a bit, or might just accellerate the shift to artillery. I don't think it will put mortek guard builds on the table, but we'll see, I'm sure some people will try them.
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Soulblight Gravelords - These are some fantastic changes. Dramatic points decreases to many units - including whopping changes like Lauka Vai down 50, Ivya down 40, several heroes down 30 - including kritza who at 70 is an incredibly cheap utility choice for scoring battle tactics who is effectively immune to melee combat. Wight kings went down in points and can now be taken as subcommanders to a bunch of other heroes, which when combined with the new field marshal honour guard is a big boon for grave guard. The unridden monsters dropped 20 points each, and the vengorian dropped 50 just like lauka did, plus there's a new honour guard ability for monsters, so there might even be something there? Probably not, honestly, like most unridden monsters in the game their warscrolls are just really bad, but I wouldn't be surprised to see some players trying it.
Overall these are really fantastic changes. The only thing I ~really~ wanted to see that didn't happen was increasing the base unit size of skeletons to 20. But while that didn't happen overall there's so many fantastic buffs here that I really can't complain. If anything these changes might be going a bit overboard, because the spite gourds really weren't doing ~that bad~ in the numbers to begin with. Which is a bit of a concern, because the Soulblight battletome isn't far out now, and if they go into it with above-acceptable tournament performance we might see some excessive last minute nerfs applied in classic pendulum fashion.
But that's a worry for later, for now things are looking very nice indeed for the vampires.
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Flesh Eater Courts - As much as the gravelords got out of this update, the biggest winners in death, arguably the biggest winners in the whole game, are FEC. Not only did they see significant points decreases accross most of their range, they also got their oratory ability back, allowing you to farm crucial noble deed points without having to commit fragile heroes to melee. The Grand Justice saw some particularly nice changes, as he's now fieldable as a subcommander AND he generates noble deed points for himself whenever he uses his ability - I expect to see him a LOT more now, which is great as he's a neat character with a fun model.
FEC's win rate wasn't all that low, but that was deceptive, because their /usage/ was really low, so the results that were seen were mostly from a handful of experienced and committed faction veterans, and even then using some pretty repetitive lists. With these changes I think we'll start to see a lot more FEC at events, more variety from those lists, and more importantly I think more casual FEC players will start seeing more success and having more fun at local tables.
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It's worth pointing out that even though all of these armies can field Nagash, he no longer costs the same points in each faction. OBR's nagash went up to 900 points, since they were the faction fielding him the most and winning the most with him when they did, likely due to having the best units to take advantage of his revival ability. By contrast FEC, who almost never fielded nagash, saw his points cost drop down to 840 for basically the same warscroll. I don't think this change will see him showing up in FEC much - he actually does work pretty well with them when considered in isolation (his 8 casts will have him projecting feeding frenzy from turn one, with 10" flying move and a huge base to put that bonus wherever you need it), but FECs mostly cheaper (especially after this update) and more fragile units don't make the most of his big revive ability, and more importantly if you're going to spend a ton of points on a giant centerpiece hero in a FEC list Ushoran's just going to synergize with the army better while only costing half as much and fitting them better aesthetically.
Anyway, we saw a lot of significant changes, far more so than I was expecting, and mostly in the right directions, so I'm pretty happy overall. However, my big hope was that we'd see significant changes to manifestations. Maybe limit them to being summoned only once per game, or maybe change them to not count as enemy models for the purpose of restricting movement and deployment, or maybe reduce a caster's or chanter's power level for each manifestation they have on the board. Something. Because right now they're more than a bit obnoxious. None of that happened, so yeah they'll still be rather obnoxious.
But yeah, mostly very happy with these updates. Probably not enough that I'll start liking 4e as much as I liked 2e - and tying battle tactics and underdog to the double turn is just balling all the things I like least about playing age of sigmar into one ugly tangled mess. But again, overall I'm quite happy.