Context: this book is a horror story anthology, set in two different settings: the gothic space-fantasy of Warhammer 40k, and the extra-high fantasy of the Age of Sigmar. There are 11 stories total.
Most of the stories are tidy and interesting. The 40k ones tend to be overall more solid, largely because the setting is far more established. This type of franchise fiction tends to hedge on you being previously invested in the parties involved (i.e. 'oh yay genestealers i know what those are'), and I felt there wasn't as much of this in the AoS ones because they're still building the setting.
Also, there's just 4 AoS stories and 7 from 40k, which isn't the best way to have divided it imo 😛
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As works of *horror* I think they fall a bit flat.
The 40k ones in particular are just... 40k stories, just a lot more dire, grounded, and personal. There's a couple in particular that pull off a good sense of mystery and foreboding (via Graham Mcneill and Peter Mclean). Possible spoilers: there's quite a bit of faction representation between all the stories, but all of them are from a human PoV
The AoS ones have the same grounded, personal scale, but I think only one of them ever managed to get a decent spooky vibe on (via Josh Reynolds). Possible spoilers: of the 4 stories, 1 is from the point of view of a non-human race. The range of factions involved is pretty narrow.
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Overall I do feel it's a recommendation as there isn't really bad stories in here, just subpar *horror*.
You'll get the most mileage out of this if you double dip in both settings. If you're just on the AoS side of the fence, this is likely a solid pass. If you're just on the 40k side, it might still be worth a go.
Really looking forward to what the rest of this line will bring!