I feel like given that we've seen Ink5oul three times now with each appearance becoming more and more concerning, there's a good chance they could be our "big bad" this season. External gone rouge perhaps?

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I feel like given that we've seen Ink5oul three times now with each appearance becoming more and more concerning, there's a good chance they could be our "big bad" this season. External gone rouge perhaps?
Also interesting that episode 16 is what I would consider a "hybrid" one with Chester reading pieces but the main incident comes in the form of video. Spoilers and theory tie-in below!
Going back to my theory about unread incidents introducing new Externals, this one being a hybrid may feed into it.
Obviously, we've met Ink5oul two other times. The first time was an unread incident (side note: also a video which is interesting) and then in episode 11.
At first, I thought this episode was going to disprove my theory until I looked toward the end of the incident in the transcript. It says:
She struggles to breathe, an alarm starts beeping. There is the sound of tearing skin and a gurgled sound, as though something were tearing itself free of her flesh. The recoding ends.
I'm going to go out on a limb and argue that perhaps Ink5oul has created a new External through this incident somehow, thus why it's a hybrid. Which, if creating more Externals or something of the like is in fact something they can do, it makes them a HUGE threat and therefore possibly the "big bad" of this season.