We've so far seen SIVA physically spreading through the environment, like the plague Bungie has played it as, but we've yet to see anything that actually suggests it truly is uncontrollable like a plague.
Behold the SIVA Orge!!!
This is the first instance in which SIVA has shown characteristics that would suggest it is a plague. (not just something the Fallen have exploited and an environment tumor)
So, what are everyone's thoughts on this development?