Before OSA captures the MC, the agent runs a DNA analysis to confirm whether he is a superhuman or not. Which means it is biological, the power is tied to the body. Not to mention the nature of the MC's power, Ava being a figment of the MC's conscience, everything indicating that this power is related to the MC's own mind, and so on.
I think I have pretty good evidence.
ava's power aren't blocked when MC power are. both in this segment and in the fantasy quest unlocking the enslaving power.
i think is more probably ava isn't part of MC mind, but an external entity trapped in is mind "cell" as she describe it.
At this point can we be sure Ava is a part of the MC's mind, after all we only have her statements as evidence and we know she's a liar.
i'm unable to find it, but in one of the earlier conversation eva describe herself like "a parasite slipping in his mind wihout him noticing it".
not very subtle, ava.
Was there anything indicating she wasn't? What was provided by the game is that she is part of the MC's mind. And even if she is something else, what kind of existence would explain everything that happened in the game so far without creating even more plotholes?
don't see any plot hole, at least any egregious one. there is an high probability ava is trapped in the MC mind since childhood (she speak of few child event), another explanation is she can access the full memory of the MC.
we see people with power interact different with people with power after they manifest them, compared the 'normal people'. ava posses some power, but was unable to interact directly with the MC before he manifest his power, because he was a 'normal person' before. this lend her lie "i'm your power make manifest" somewhat convincing.