My theory is that the Orz are some type of ID beings that
were attracted to the Androsynth because they were synthetic
beings, and not human. They had a different smell than humans,
something the Orz desired. This might be why the Orz are in
suits... maybe there's some connection between them and
technology, which seems to be a great theme in the SC
universe (the Mrnhmrnmmm, oh whatever). The Orz obviously
wanted the Synth for some purpose.  Nefarious or not, we do
not know, but we can assume it may be innocent to the Orz,
but perhaps detrimental to the Synth.  As for the battle on
the Synth home planet, I would guess that they fought with
the Orz (or some other ID race), but their weapons were
ineffective being that they were trans-dimensional--"ghosts"
or "phantoms" to the Synth. So the Synth did what they
thought would save them--use nukes, which obviously didn't
work.  After the dust settled (they might not have been
nukes, since the game says "within the last 5 years," and
it wouldn't be safe for anyone to walk around a 5 year-old
nuke site), the Orz stole or borrowed or assimilated the
Synth.  I think "below" refers to their dimension, perhaps
sinister (humans would interpret "below" as maybe Hell,
whereas Quasi-Space would be "above", or heavenly... just
a notion from a linguists POV).

What my question is, though, is why did the Ur-Quan
eliminate all those historical sites, and does it have
anything to do with the Arilou and their visiting Earth?
I think this concept was borne out of people thinking the
Pyramids or Stonehenge are of cosmic significance, maybe
beacons for other creatures or a source of power, divine
or otherwise.

I guess to bottom-line my theories, I think the Arilou and
the Orz have more of a connection than just being from ID
realms. I think it's obvious by reading between the lines
that the Orz are sinister and the Arilou are benevolent.
Or that the Arilou are what humanity evolves into in the
future and the Orz are what the Androsynth evolve/hybrid
into in the future.  Once upon a time I had a Star Control
II hint book that came with a big starmap and details on
every race, including the Taalo and the Gg (does anyone
else realize on a kindergarten letter chart that Gg is
just the example of how to write an uppercase/lowercase
"g"?).

Again... all theories... but fun to speculate. The best
forms of fiction are when we DON'T know the real answers,
or there are 1,000 possible explanations but all seem
to contradict, leading to an unexplained mystery. Hey,
it worked with The Matrix movies and The Sandman comics.

Oh yeah, and Picowoof needs to chill out. You DON'T know
because you didn't write the story and therefore everything
in this forum is all theory and suppositions. There are
no facts in fiction. It's just a game, and this is just
a message board. Show some maturity and stop attacking
other people.