Morovir

There was a Stormcast Eternal when AoS first launched and a Slaughter priest when WD first went back to being monthly to promote the Gorechosen boardgame.

Exactly - it's precisely the same amount of influence that they get from any of their other cultural influences (i e very little), and so defines them just as much

In fairness, the most iconic Medusan weapon in the Horus Heresy books is the Medusan Zweihander, a weapon that is just as Greek as the Tetsubo. The truth is, the Iron Hands have never had much of a cohesive iconic weapon other than Iron Hands = Mechanicus = Cog power axes and one thunder hammer from a 20+ year old upgrade kit. The Greek theming doesn't go beyond the name Medusa and the Gorgon, and it could be argued that they have just as much Scottish influence from the clan companies, and the pre-Primarch origins in Old Albia. Combined with Medusa apparently having Zweihanders, we have a Greek named world with Scottish themed clans and Germanic weapons - can we really argue that the addition of Japanese theming is truly so much of a departure from their existing cultural melting pot of an identity?

To be fair re. the flak vests, they've been on Catachan models since the Catachan Command Squad was released in 2009?, so they're not exactly a recent development.

If I remember correctly, it was returned to the Iron Hands in return for them accepting the Codex Astartes (per Nick Kyme's Rebirth), and then it was kept in the centre of a maze at the heart of the Eye of Medusa guarded by a Helfather (rumoured in-universe, per David Guymer's Eye of Medusa).

He broke it in their first duel before Istvaan, then reforged it and wielded it against Fulgrim at Istvaan, after which Fulgrim took it off his corpse.

That's mainly because in the last edition, an Iron Father came with a servo arm rather than a machinator array - I'm assuming it changed to make it more of a difference from the Warsmith.

I think the split is probably to split up the bolter/bolt pistol and chainsword option for Noise Marines from the sonic weapon Noise Marines, by rebranding the former as their Legionnaires and leaving just the sonic-armed ones as Noise Marines.

Those are the big sprues from Indomitus/Leviathan - they aren't sold individually.

Might not even have to recut for the Ogryn - each one is on its own sprue in the box (with Nork's pieces spread across the three sprues) which could allow the Ogryn to be customisable.

Not Uriel Ventris, Aeonid Thiel. He appeared in the audio drama Censure by Nick Kyme.

Pretty sure he uses one in both Little Horus and Vengeful Spirit.

Well put - other than the fact that it was Phil Kelly, not Nick Kyme, who wrote that particular atrocity. Looking forward to this one - guessing failure must have had it's consequences given that Areios was a Captain in Throne of Light.

A quick reminder to anyone who wants a taste of what Collins' Eidolon is like that he already has a short story, Primacy, out, which is set between Angel Exterminatus and Path of Heaven, and which I would heartily recommend as a book showing Eidolon's competence. https://www.blacklibrary.com/the-horus-heresy/quick-reads/eshort-primacy-eng-2023.html

I think the story you're looking for is the novella Scorched Earth by Nick Kyme, which you can buy on its own as an Ebook or as part of the 50th Horus Heresy book Born of Flame. Hope that helps!