I think you might be close, however I would put forward a slightly different theory. My theory: The Traveler is the source of the Vex. There has been much speculation that the Black Garden was originally supposed to be "Inside" the traveler. Also, the speculation indicates that the traveler was actually evil and the source of the darkness. I think, in some fashion, as you suggested, the Traveler soaks up and absorbs "light" and uses it to power itself and the Vex. In game, and in the grimoire, there is lots of speculation as to how the vex are powered and connected. What if, the Traveler is the Vex Power Source and Central "Mind". It absorbs light and powers the vex "network" with it. Look at the vex themselves, the vex weak spot is typically a whit light, when you kill them white light "spills" out ins some sense, the confluxs are also white "light" structures. The vex architecture is also similar to the traveler and there is a theme of concentric circles permeating vex "artwork" if you can call it that... Most of the vex architecture is geometric squares and rectangles, but where they have anything that could be considered to be "decorative" it seems to be circular, also the portals resemble the traveler in appearance and "look". Here is a link to some bungie early vex concept art... http://dorjebellbrook.blogspot.com/2014/10/destiny-early-vex-exploration_9.html Look at the second pic down... Remind you of anything? Vex Teleportation: We know the vex can teleport across space and time (entire star systems), but I doesn't seem like they can just appear anywhere. Otherwise, they would be on earth... Right? Maybe the Traveler sets up a network, almost like a Vex Internet, and the vex can travel anywhere or more likely, materialize anywhere in the network they are called for. The vex seem to act exactly like the Agents from the Matrix... The Vex might not even be "entities" but a physical manifestation of a digital network (I mean they aren't like individual robots built on an assembly line and networked together, but a artificial manifestation of matter controlled by the AI network) In that sense, The Vex don't actually "teleport" but are just materialized and de-materialized at will of the network. Again think of Matrix agents, they aren't "real" they just are input into the world as a physical manifestation of a computer program. This could explain how they teleport and seem to come in virtually endless supply. (I know other enemies also teleport, like fallen captains, but when they move, it is different,) they seem to vanish and re appear in a new spot like the warlock blink, the vex seem to dissolve and re assemble in a digital like fashion.) The Vex / Traveler connection: The Vex are everywhere the Traveler has "been". The traveler first visited Mercury, (says this in the Grimoire or somewhere, cant remember exactly where...) The Vex were also first seen on Mercury and "turned the whole planet into a Machine" - per dinklebot if i recall. The traveler has also been on Venus and Mars, also now infested with Vex. The traveler is not on Earth, and there are no vex on Earth, Yet.. But, The vex may be something the traveler leaves behind after, to continue its "control" or spread its power and influence. The hive, cabal, and fallen are all fighting the Vex, and you, and each other for the most part. But here is where I really like your theory, it explains why they all came to our solar system. Each of the hive, fallen, and cabal come from far off solar systems, maybe even other galaxies... Why are they here? Perhaps they are following the Traveler to destroy it or contain it from spreading? If they had their own home worlds devastated by the traveler and are now over run with vex they could be either trying to find a new home world, or destroy the traveler, in order to free their home worlds from the vex. If the Traveler is powering and controlling the Vex, destroying it might be the only way for them to reclaim their home-world. I think this is underscored by the fact that each race is primarily interaction with the guardians and the vex, not so much each other. The Hive and Fallen fight each other, one mission they invade the hell mouth, perhaps they were fighting over the travelers shard that the hive was experimenting on? There is a lot unexplained, and these theories seem to piece some of the back story together and make it all makes some sense. Lastly Vex and Guardians: The Vex don't seem to be trying to actively subvert the Guardians. Any interaction the Guardians have with the Vex results from the Guardians venturing into vex territory and messing with things. They only attack us when we are in what may be considered an offensive operation. We are either in their territory, messing with their confluxes, trying to summon and kill their gate lords, entering the vault of glass, ect. The Guardians are always on the offensive. On the other hand, the Fallen and Hive are invading earth, attacking the guardians, cabal are invading mars and attacking human settlements and occupying human ruins there as well. The Vex seem to be just existing and guarding their shit. This leads me to believe that the Vex are tasked with doing some job, which does not directly involve defeating the guardians, they only fight us b/c we are always attacking them or invading their bases. If the traveler was controlling the Vex this would make perfect sense. Why would the Vex fight us if we are aiding the Traveler? Well they don't, unless we are trying to hinder the Vex. AKA they are defensive but not offensive against the Guardians, they do however seem to be attacking the other races. For example they are invading the house of winter on Venus and trying to kill the Archon. This of course is all conjecture based on my observations, but if true, would explain a lot that is otherwise unexplained.