: So, could the Harvester in fact be more Precursor than anything else? It
: definitely doesn't look Forerunner to me, and only Covenant in passing.

I'm going to say the Prima guide is erroneous. I checked the Visual Guide and it mentions that its organic design is due to its origins on Hesduros (the planet of politically-removed and religiously-motivated Elites who formed the core of Jul's Storm faction of Covenant.) Viewed in that respect, you can see similarities between the harvester and some of the Storm's armor--take a look at the Zealots in Halo 4, for instance.

It does look very alien from stuff we've seen before, but I think a large part of that was just due to the color grading in the level--splash that sucker purple and it's not as far removed as it "feels", I think.