The Garlean Empire vs Omega

[Necrotica]

Even with his body and the eyes completely destroyed, there is a certain amount taint remaining in Estenien that threatens to take control.

Is this stated in the game anywhere?

[Zero-ELEC]

If anything, elder/more powerful dragons are almost a viral/lycanthropic creature able to exert a certain amount of control/power simply by having the blood mixed in another creature. And, should the host be of a certain strength it seems they can control the dragon's power.

Honestly, that seems to be the case with dragons in general, when you think about. An asexually reproducing alien species, whose blood can turn others into them when flesh is consumed, whose powerful individuals can compel others of its species and those close in nature (scalekin) through song. Change a few details and you've got a pretty compelling sci-fi viral alien species like the zerg or tyranids or xenomorphs of something.

[Alleo]

Is this stated in the game anywhere?

I am not sure if this is outright stated but we do get hints that Nidhogg is still in a way with Estinien. (Not sure about the "threatens to take control part")The way he talked with Tiamat. How he was able to see the souls of the death dragons on Ultima (just like the WoL), stuff like that. Of course you also have his attacks that are fulled by Nidhogg too.

I guess this could go many ways but it does feel like at least a bit of Nidhogg stayed behind. Maybe part of his aether.

[Necrotica]

I am not sure if this is outright stated but we do get hints that Nidhogg is still in a way with Estinien. (Not sure about the "threatens to take control part")The way he talked with Tiamat. How he was able to see the souls of the death dragons on Ultima (just like the WoL), stuff like that. Of course you also have his attacks that are fulled by Nidhogg too.

I guess this could go many ways but it does feel like at least a bit of Nidhogg stayed behind. Maybe part of his aether.

I see how that could be attributed to being Nidhogg still. I just figured he had been semi dragon aspected/fused/genetic rewrite type thing but it was just general draconic nature not specifically tied to Nidhogg. Like how some of a person's traits are tied specifically to their parents but others are just a natural part of being human.

Nidhogg made him more dragon like, maybe not specifically more Nidhogg like. Also whenever he 'talks' to Nidhogg I think he is talking to his weapon still coated in the blood.