It's a real pity I absolutely LOVE the majority of the book, the world building and the section on the Neomorph in particular is magnificent, perfect understanding of the creature as it is in the film. And the section on the Engineers I could go on about, but I'm disheartened because the parts actually concerning the Alien itself?
Not as palatable.
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My one major issue is the nature of the Alien itself funnily enough, I don't see the need for all the "unique" versions, a great deal of them unhinging the realism the book so perfectly set up beforehand. The Weaver for example is entirely unnecessary, not great for something named "The Perfect Organism" - I do like the addition of the Stalker though, although it's existence I think required a clearer description.
For instance, I think in the Egg section it should have detailed three types of Eggs.
The regular one, producing the regular (Soldier) Alien, the Praetomorph Egg producing the Stalker Alien and the Praetorian Egg producing the Praetorian Facehugger- and perhaps go for the more believable terminology the Neomorph section used.
Why have three unique names for essentially the one thing changed slightly?
Why not just for the Soldier have "Soldier" and then "Armoured Soldier" for instance?
And for the Scout, "Scout" and "Armoured Scout" then?
And for the Charger, isn't it essentially identical to the Praetorian but just quadrupedal instead of bipedal? Why not merge them into the one creature?
In a story for instance just a Praetorian or two that were intended to be Queens just have to stay as is because a Queen is already present?
While I understand the "Royal Jelly" nonsense, might be useful for gameplay and all the castes, I don't think the believability/tonal/plausibility trade is worth it.
Not sure how I feel about companies actually obtaining the Alien, nor the additions to Acheron LV-426;
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The idea the Derelict survived, ambiguously. Instead of directly connecting it to The Cold Forge, or declaring it destroyed completely.
Fiorina 161;
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Three Eggs in the bowels of the facility, Andrews, Boggs and Rains ovomorphed.
Or particularly LV-223- The inclusion of the awful Fire and Stone series continuity in particular is immensely disappointing, as is the referencing of the Pathogen as an "Accelerant" something retconned by Covenant. It's honestly totally took the wind out of my sails in regards to the book...
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Empress, okay but also Queen Mother? Also Alien King? Really? Seriously?