I can't see the phase Diagram
. The link thats me to a blank page.However Some ideas on the comments raised.
I believe that mycetic spores contain entire broods of creatures. It is possible that the creatures are not fully grown. Instead the spore, supplies them with nutrients and they rapidlymature, within minutes they first lot reaches full size, as the spore lands.
It then grows roots to aquire more nutrients and the rest of its cargo are grown. Thus a spore slightly larger than a marine drop pod could carry a few score gaunts.
(this idea is an extrapilation of mine after reading warrior of ultrima: first space battle)
As for the larger boyz. They could use a similar concept. Since they don't appear in the initial assault. It is possible that drop eggs are.. well dropped into areas that the nids have gained control of. These rapidily grow into the biotian and BWEs. Not quite sure hw you get a norn queen down there to ride the dominatrix though.
Another idea is that smaller drone ships ebnter verylow orbits (other races escorts can land so ours should) and then "deposit" fully formed biotitans (Ref: storm of iron). Again the area will need to be held first, to avoid losing the bioship. This way avoids energy lose in the whole build-dissolve-reclaim-dissolve cycle.
As for genestealer cults fighting a hive fleet. It is possible. In a WD about 3 or 4 years back their was an article about how creatures from different hive fleets have difficulty understanding each other (ie a warrior from kraken might not be able to co-ordinate hormagaunts from beamouth).
Thus if a hivefleet stumbles across a planet that has a stealer cult from another fleet,they will only see it as food (since hivefleets do attack each other). However if the parent fleet comes along (or a closely related one) then the genestealer cult will come under their control, by the hive mind controling the patriarch who controls the cult. Remember that patriarchs send out psychic homing beacons when the cult gets to a certain size. They are not independant. (Okay I have a theory that says some of them are but that isn't offical canon, heck it isn't even writen down, but it combines RT stealers from Ymgarl with the modern incarnation without saying a warpstorm did it).
Lack of brain
consumption: Perhaps as the nids have no groud to space craft that we know of, the largest hive nodes will grow out of the atmosphere and hive ships will kind of dock at the top so material can be brought up to the fleet like a space elevator
Ie become capillary towers. Indeed this is how fluff says the planet is eaten, sucked up though a straw.
. Thanks Hena. One major comment on crashing hiveship.
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