Question about ubermorph?

[Solid Gamer]

I played long time ago and replayed this great game again. Only a question: after the "eye operation" part of the game the ubermorph jumping into your room.

Does big marker sended it to kill me? (cause he knew we work with Nicole now together?) Or he was just nearby and came by coincidence???

[TwistedTenure]

I'm not one to care a jot about story in games; I play for gameplay, so I may be missing something, but as far as I see it the manifestation of Nicole is as much 'of the marker' as all the necromorphs.

Don't forget, she is a manifestation in Isaac's mind (he who is supposedly suffering from a form of deadly psychosis, so, hallucinations etc [fill in various other trite notions of psychopathy here]) as a result of the influence of the marker.

The necromorphs are [insert contrived story for monsters' creation here] ... as a result of the influence of the marker.

There is no logic because the devs just made that moment for the sake of ramping up the drama at the end; the rest of the (contradictory) game simply for the drama. Given that I generally don't give a toss about story, that's fine with me because it's all great gameplay.

[Xenos]

The Necromorphs are the first stage in the life cycle of the Bretheren Moons, colossal necrotic entities the size of moons and equally as unfathomably intelligent. The Marker is the creation of these Moons, designed to raise up sentient life from nothing with its signals, and then turn that life into Necromorphs once they have become a sufficiently sized population. During the Convergence Event, all the Necromorph tissue and surrounding land is dragged into the air to form a new Bretheren Moon. This requires the absorption of the Marker's creator, likely for ritualistic reasons or to finalize the process.

The hallucination of Nicole is NEVER your ally. She is a false apparition shown by the Marker to manipulate Isaac into doing what it wants. First, she destabilizes his mental state by constantly hounding him and attacking him. Then, when it's clear Isaac is going to make it to the Marker, it changes its strategy and makes Nicole an "ally" to Isaac in order to lure him in, which works because Clarke has taken such a mental beating he isn't fully sane anymore. The end goal is to consume Isaac during the Convergence, it doesn't have to be consenting. The Ubermorph is another, final attempt to kill Isaac and absorb him by force, since if he dies he becomes a Necromorph like all the others and the Marker can complete the Convergence. Since the Ubermorph doesn't succeed in killing Isaac, the Nicole hallucination is the last possible attempt for the Marker to try and kill Isaac to absorb him. Since that fails, and Isaac survives, the Convergence event fails and a new Bretheren Moon isn't formed.

[Play2603]

If you look closely you can see the Ubermorph walk into government sector when you cut the power. I guess the Ubermorphs are there to protect the marker, its bodyguard.
Did Dr. Mercer learn how to create a regenerating necromorph from the marker or opposite?