Can you please point out where I said they were created to fight Guardians? That is not the point I was intending to get across, and I want to make sure everyone has the right idea.

it is theorized that Aphix Invasive's primary function is to oppose Guardians.

That would be talking about a specific Vex programming subtype, not the Vex overall. Subtypes are their own algorithms and each have their own purpose. Hezen Protective's is to guard the important Vex structures on Venus. While Aphix Invasive's specific task is unknown, it is [u]theorized[/u] that their purpose is to oppose Guardians. This is possible because we see Qodron arrive in the Prison of Elders with an army of Aphix Invasive Vex. Qodron comes to the prison of his own free will because he knows that Guardians will one day be there. Thus, it stands to reason that Aphix Invasive is specifically dedicated to combating Guardians. Obviously, this is just a theory and is not solid fact.

I dont think it would be just against gaurdians but the aphix incasive are used as an invasion force for new planets and areas so they can set up gates for the rest of the vex units which carry out whatever process tye area was needed for. Its likely the aphix invasive study the area and organisms around them relay that information may it be available resources of a planet or the type of life living there. They may very well be using them to learn about gaurdian fighting strategies and how to best counter them, giving them a new use to the vex if not to be used for an invasion of Earth later in the game. Hence the name "invasive"

I would agree with you except that there have been Aphix Invasive sighting in areas with a well-established Vex presence, so I don't think that's their purpose.