Why does everybody think that every exo is rasputin? Just because they're robotic? You know what you guys are?? Racists! [spoiler]Incase you didn't notice, that was satire, but anyways on to the real topic... The exos were made in this HUGE facility or factory of some sorts on Europa. What backs up this theory is Cayde-6's backstory, he talked about him having debts with Clovis Bray and they turned him into an exo (with his consent of course) to repay them, he was like the main object of an experiment i think. So he remembers waking up on a a place he was unfamiliar with (Europa) and had a view to another world (Jupiter) and standing in front of this huge dark creature and it talking to him, which at first i thought was an embodiment of the Darkness, but now i speculate it was an Ahamkara because they inhabit the Jovian worlds.[/spoiler]