This made me think of the factions in the tower. The faction leaders expressed their philosophies to respond to the coming darkness. this video from dattodoesdestiny has clips from the faction leaders: https://www.youtube.com/watch?v=F7HRgOwzr_M&list=UUkmAjbIecTIjTQctolYeuDw&index=2 Dead orbit wants to run and hide from the darkness - they remind me of the hive The new monarchy wants to build a new kingdom - they remind me of the fallen The future war cult that wants to fight until they are wiped out - they remind me of the cabal or their obsession with another timeline reminds me of the time traveling vex. Perhaps the characteristics of the enemy species we encounter are a representation of choices those species made when they encountered the darkness. Or maybe in some weird way the species we fight against are actually ourselves from different timelines where we made different choices.

I do remember that the first thing I thought of when I saw the traveler, was of a terraforming module.. but for what..? I do like the theory of the hive being fallen, and I assume we'll see more hive zombie types.. perhaps we'll even see hive infested guardians...

I highly doubt that the Fallen and Hive are related in any way. The Fallen do not directly serve the Darkness, for they fight the Hive--and the Hive embrace the Darkness and revere it. The Hive are undead. They are not an infection or biological entity like the Flood from Halo. They are necromancers who have used the power of the Darkness to keep themselves alive for eons--they are directly inspired by fantasy undead. The location of "The Summoning Pits", and the mention in a patrol mission that "space barnacles" are biomass grown by the Hive makes me think they grow corporeal forms from this biomass, which they in turn bind summoned souls of old to. They are an ancient monarchy that has preserved their hierarchy through millennia of undeath. Thralls, Acolytes, Knights, Wizards, Ogres---and perhaps more enemy types we haven't seen. They are a race of liches. Why are they undead? Perhaps they hit a snag in their own evolution when they were truly living, and turned to the Darkness to preserve them as they saw it as the only way to escape extinction. Or, perhaps they were so corrupt and greedy for eternal power when they encountered the Darkness that they simply embraced it. The Fallen on the other hand are completely biological. They don't show any signs of being undead despite their souls escaping from their bodies when killed. They had a grand past which they scarcely cling to; they are now nomadic barbarians that pick apart whatever they find. They assert what's left of their former authority and nobility onto whoever gets in their way, for they have claimed all of our former worlds for themselves. They think they are still entitled to riches and glory, and since they have none left, they resort to forcefully taking it from others. They are divided amongst themselves into five Great Houses. Unlike the Hive, their physiology is different. Their limbs may be similar, but their head shape and eyes are very different from the Hive. The Hive come in all shapes and sizes--the twisted frames of the Thralls, the hunched-over Acolytes, the upright (and tough) Knights, the floating Wizards, and the Giant Ogres. But the Fallen (apart from their servitors) have the same basic shape across their ranks. Also, it's highly likely the Fallen's current nomadic raider behavior is a much more recent development than the Hive's necromancy. I still don't think there are enough similarities, even for them to share a common ancestor. Their origin stories are just too different.

Here is a theory for you... What if the Traveller is nothing more than an AI in a terraforming ship, sent ahead of a colony ship. But somewhere along the way the colony ship doesn't arrive. Terraforming ship decides to find someone else to help colonise worlds... Traveller finds us... but what if ANOTHER Traveller was out there... a Black Traveller who terraforms the planets the Fallen originally were on... before they became the fallen. The terraforming engine infects the Pre-Fallen and create the Hive... which is why the Hive and the Fallen are fighting... The Hive drove the Fallen from their home planet and then follows them. The Fallen will then hate the Terraforming ships... including our Traveller. The Hive just plain hate everything, being space Zombies after all.

Did everyone forget that the hive make temples on the moon giant spaceships and all that sortve stuff? I don't think the hive are zombies I think more like the aliens from e movies: alien vs predator and aliens and such. I mean they wernt zombies but they had a queen made structures had classes and so forth "Ty god they didn't make spaceships D:" just like how the predators made the aliens I just think the darkness gave "it's light" to the hive to make them a sentient specious but I don't think they're zombies and I think the two armed fallen are females they're smaller n there body structure couldn't spport two extra limbs and they have a Mohawk I think they're females and the four armed ones are males btw hope this cleared up this whole confusing thing about the hive being zombies

Why is everyone so sure that the fallen is the hive? You do realize that the hive actually are insect like, and so that the thralls are just simply worker ants for the colony? No brain required for lifting a pole. Acolytes are actual overseers for the thralls, knights are the "titans" of the hive, wizards or commanders, most likely with an actual brain, used for coordination of hive forces. Orgers are literally tanks, looking at one chained in a video, most likely completely brainless, and need to be carefully monitored so they don't smash other hive. Great chance of a queen because of eggs found. Also, why would they want to convert other races? They despise other life, and want to eradicate it all. Their crusade of darkness? Am I the only person who watched the video for them?

Maybe the traveler gave several of the races its light once and they misused it? Now they are trying to destroy humanity in fear of our capabilities.

my theory is that the darkness corrupted each species to become evil... like i saw an interview where someone said that the fallen used to be a good species, and now are bad. As for the Hive, the Darkness infected them into space zombies...

Space zombies? (This is very similar to yours) Fallen? Ok, the fallen are only similar to hive thralls. So I think wizards or high powered hive leaders resurrect the dead dregs and vandals into hive thralls and the rest of the hive is it's own race, now let me go more into this. Why? I think this the rest of the hive behavior is smarter and they get behind cover. But the thralls go in and attack like what I have seen from the fallen the most. And the acolytes and wizards look very different from most of the fallen and hive thralls. I bet your saying "Pro this makes only 5% sense" well hive wizards are dark, evil u could say, and makes most sense if they use black magic. In the list of spells that are considered "black magic" is resurrection. Do u see it yet? No, well let's move on to why I think the hive are there own race. I have 2 theories for the hive so let's get in to it. The hive could be mutated fallen guardians wizards=warlocks but this very doubtful. On to the more likely theory, the hive are a wiped out civilization that has been mutated and brung back by something, the traveler…, and they now work for that thing and has to do it's biding. Why I think it might be the traveler. The traveler might be a living being. Since the the city is waiting for it to wake up and the traveler is simply tricking us by bringing on the golden age. The traveler is the darkness controlling the hive, cabal, and fallen. And the vex came to stop us cause they know we will stop the traveler so they went back in time to try and stop us cause they think the traveler is good like we do. So the vex is created by what ever lives in the future. Now back on to the connection between the fallen and hive. One last piece of evidence, the hive have big green eyes, but yet the thrall don't. The fallen when they die maybe their eyes decay fast along with their ears or hair depending if they are a dreg or fallen

The support base centered here was likely the first off-Earth colony, though it has long been left to ruin. In the centuries since, Hive temples have begun to breach the surface, exposing entrances to their fortress below. [b]It was here that we came face-to-face with Crota and his legions, a force so powerful we abandoned the Moon.[/b] Now Guardians venture into its depths seeking revenge, most never to return. the hive have been on the moon before ?

I think it's a coincidence that the Thralls and Dregs/Vandals look the same it's possible that they originals wanted the Hive to be space zombies that resurrected dead species like the Fallen. However if that was the case they'd be adding humans and guardians to their ranks along with the Cabal but they aren't. If you look at the Hive they all appear to have exoskeletons, They have rooms filled with egg sacks ,and have a tiered hierarchy like a monarchy; you have the Thralls which means slaves, Acolytes meaning assistant or follower, Ogres meaning hideous man eating monster/giant, Knights meaning someone who serves a sovereign lord, Wizards meaning someone with magical powers. The Hive sounds a lot like Arthurian legends by that tier system and since they're the "Hive" which is something created by insects and going with their exoskeletons, egg sacks, and tiered hierarchy everything points to them being insects so they must have a King and Queen that we haven't seen. Also I just remembered if you kill a Wizard the other Hive under them usually die so they must have a psychic link or something similar to what most insects have and the Wizard with their powers are a lightning rod for that link picking up the signal from the Queen and King and sends it to the Hive beneath them and vice versa so when the Wizard dies and the Hive dies with them that's because that psychic link shuts down and they don't actually die but go into a hibernation state until another wizard comes by.

I don't know what's in them, but in the moon, there is a massive chamber filled with rows upon rows upon rows... you get what I mean, of cocoons, eggs, or something on that line. So it's completely iffy on what the cocoons are for, but I believe it would most definitely shed some light. Maybe the cocoon is where they do take the dead, or maybe they are egg sacs laid by a queen. Which supports why there are such large spaces, the mindlessness of the thralls, and why they are expressed as knights, acolytes, wizards, etc. But if there is a queen, I bet there is a 50% chance of a king, and I don't want know how strong that is.

They have similar humanoid anatomy because that makes it easier for the game developers to create animations off of the same framework. My 0.02$.