Early heresy emperors children.

[incenerate101]

What armor version did they wear when they fell to chaos? Was it mk v? And what were some of their symbols and such?

[AnEnemy]

2-4 just like everyone else I would imagine.

[Eberk]

I remember an article in Index Astartes about the Emperors Children where there was some talk about the pre-heresy actions... even had a 'picture' about a pre-heresy EC marine and its legion marking

Have you already read that ? (perhaps google can help with)

[fuzzbuket]

purple, gold ornementation, AQUILLAS ACROSS THE CHEST (only legion allowed to do that) and the symbol was still the wing/claw but it was less chaosy. and wearing the same sort af armour as the rest of the legion. HOWEVER there would be more variation/newer marks due to the fact that the legion was like 10 times the size of the other legions.

[Tzeentch's Dark Agent]

I know that they favour MK 4 in particular

[Wolfshade]

In Delieverance Lost, they do infer that the traitor legions have had more "modern" armour compared with their contemporaries. Mk4.
Though don't forget they had their own forgeworlds and could acquire the templates of more modern armour

[Wildeybeast]

SPOILERS.

Mark 4 is being made on Mars in Mechanicum and supplies are being shipped out to the traitor legions in much greater number because the Fabricator General is in league with Horus. The loyalists are moaning about this before they realise what is going on. When Mars breaks out into civil war, the Imperial Fists evacuate as much mark 4 as they can, most of which is given the the RG in Deliverance Lost. When one of the RG questions what happened to Mark 3, the IF explain that the cobbled together and converted stuff the RG made on Istvaan has been adopted by other legions as Mark 3 due to the lack of Mark 4. This means that Mark 3 is actually likely to be a mixture of Mark 4 and mark 2 as the RG took a lot of the traitor's stuff and it is reasonable to assume some of them would be wearing mark 4.

So, to answer the OP, heresy era Emperor's children will most likely have a mixture of Mark 2 & 4, given the mark 3 pattern is used by the loyalists after Istvaan, it is unlikely they would have mark 3. If you want to know what they were wearing when they are first corrupted in the novel Fulgrim, it's likely to be mark 2. The timeline seems to place that event more or less alongside Horus' fall, with the corruption of Mars by Horus coming later on. Mark 4 is very new at the beginning of Mechanicum, so it would be unlikely the EC had it when they were first corrupted.

[Cpt Codpiece]

the raven guard were given MKVI suits in deliverence lost, as they had been prototyping it, they got the first batch, it was a joint operation with mars and earth, alot of them were made on earth/.terra if i remember right (the IF guy tells corax and bran, when he delivers the 1st batch).

this is the reason MKVI bears the corvus moniker.

but yeah EC are mentioned in the books to have MKIV maximus suits, and so do the mournival in PA (loken, torgaddon and aximand)

[incenerate101]

Sweet guys thanks so much. Now I can confidently purchase accurate armor from FW!