#god devouring serpent

1) Placidusax was an Elden Lord, so his 'god' that was fled, was likely the same as Marika was a God. There is a very humanoid statue of a lady surrounded by triple wolf under depiction of primordial Elden Ring though

2) The lady has same Slavic aesthetic as Rauh people

3) Area where we find the Gelmir's Serpent-God's Curved Sword also has Rauh connections: Makar is a Slavic (Russian) name, Makar is literally fought in the area full of Rauh ruins and architecture, the unique bat lady wearing a kokoshnik (again, a Slavic headwear) is found in this area too

4) Magma Wyrms are people that do Dragon Communion, ie eating hearts of Drakes. There are four Magma Wyrms; one is Makar, another found in the mountains of Gelmir, another found underneath Gelmir mansion, the last one is a troll Theodorix. That makes 3 out of 4 Magma Wyrms be connected with Gelmir, Makar is a middle point

5) Dragon Communion is the practice taking roots from Farum Azula

6) Now-extinct Gelmir Cult has Temple of Eiglay with a Godskin Noble in it, and one of the man-serpent variants straight up copy GEQ's Godskins style

At the same time, Gelmir has depictions of a half-serpent half-bird

6) Birds, specifically hawks, are allies to Farum Azula, same as Stormveil

7) Eiglay and Winged Serpent appear to be related, as eyes of Winged Serpent and man-serpents are the same kind of green:

*According to the person that datamined textures ( x ), man-serpents do all have green eyes, but those except for Rya have the additional filter going over their eyes to make them darker

You can see with Melina's purple eye as an example that sometimes additional filters are used

8) Winged Serpent has dragon wings

9) Godskin Apostles turn their flame like a whirlwind, similarly to Banished Knights and all alike

10) Godskin Apostles and Nobles are both half-serpents; Apostles stretch and spin similarly to man-serpents and Nobles not only have a snake tail, but also they are not actually "just fat"! They are very long snakes that simply coil underneath rather than stretch in and out:

11) GEQ is consistently depicted as serpentine, and is the reason snake is seen as traitor of the Erdtree as it could not have been Messmer (snake traitor is addressed by Godfrey's Duelists, and Messmer with his knights were clearly on good terms with Godfrey)

12) Unlike in Dark Souls, in Elden Ring, snakes are not genetically connected with dragons

13) UPDATE: I forgot to mention that Godslayer's Seal has an Obsidian in it! It is not only in localisation, but in the original too - 黒曜石. Obsidian is a natural volcanic glass, so it is another point of connection with Gelmir. :>

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So how about this:

Placi's God was a Rauh royalty, who was fled to hide in Gelmir (escaped Bayle's wrath?) along with multiple other people, and discovered Eiglay in there! Perhaps, Eiglay ate her (which is why Placi's wait is futile), instilling fear into people that now bent their knee and formed the sacrificial cult around her. Fear can turn into reverence very easily and faith can be a fickle thing!

However, some cultural aspects as allyship with Stormveil and Dragon Communion remained in this new culture. Female monarch would be a kin to Eiglay, birthing serpentine people and, as ideal result, the Winged Serpent. It inherited wings as genetic trace of Dragon Communion. Gloam-Eyed Queen was the last kin to the Gods Devourer, though seems like not quite like Rykard as her depictions are obnoxiously humanoid and her Godskins are half-human. Maybe she had smaller Eiglays as part of her body, same as how Messmer got small Winged Serpents as part of his?

After being chosen as an Empyrean by the Two Fingers, she mirrors Marika, owning Scadutree that was planted together with the Erdtree, and "proper" Death Flame that is "gold accompanied by shadow". Upon creation of the Golden Order, Rune of Death, ie Shadow, was separated from the Elden Ring, severing GEQ from the equal position from Marika as Marika had no interest in letting Death have its natural power in her Order and intended to live forever. Expecting GEQ to do her own thing and be no longer of a threat backfired, so it took Maliketh to further severe GEQ from even her fragment of the Elden Ring, the Death Rune.