There is more than enough fluff in the codex on heamonculi to fill in all the gaps.
The power from pain gets worse with time, not everyone can rise to the ranks of an archon to get fed a couple of thousands souls every day. Vect is a couple of thousands years old, and he'll keep going till he's killed. He stays young as long as he's the king of Commorragh.
Normal dark eldar can't afford this, thus become heamonculi, still leading figures in Commorragh.
Lore from most novels is worthless, BL books arent' considered real GW fluff, though BL is a part of GW. Only the 3 last eldar/dark eldar trilogies are actually good eldar related books with fluff accepted by the community. The 2 writers were 2 major contributers to the old rulebooks and codices. Sadly all the previous books containing dark eldar were really bad, in fact their portrayed the DE as being chaos worshipers, even Lelith herself was linked to this T T.
Anyway, even if you start from scratch, any dark eldar will eventually go mad and start mutilating himself (wrackstyle), with this it will get bad enough to get to the point were a heamonculus is born.
Bodymodifcations amongst eldar (all eldar) are not uncommon at all, it's not just the dark eldar, far from it. You have somo fluff on this in the Path of the Outcast, a ranger openly declares she has modified her body at some point. Why? Because she could.
Now back on the power from pain.
Who is the oldest dark eldar known to us? There is an answer: Urien Rakarth
He's the first to discover the secret behind the ressurection/regeneration technique, he mostlikely started to test the true potential of the power from pain the dark eldar gained after the fall.
Urien is older than Vect probably, he's probably also one of the first heamonculi in Commorragh, though again the real origins and birth of the first heamonculi remain a mystery.
- Quote :
- I have read, as far as I know, all lore available from wikis and from novels outside of the codexes concerning Dark Eldar.
I get the feeling it may be they rise from Wracks, but I don't remember it being elusively stated. That being said, its been a while since I've done my research.
There's a huge difference between reading and knowing by heart, I've read the codex so many times I've stopped counting a long time ago and I keep doing it for the pure fun because of the cool fluff. I'm not the only one who read his codex several times, that's how you get really familiar with the fluff. No offence but you wouldn't ask such questions if you had read the fluff on heamonculi several times like most of us.
The quotes from wiki are just codex fragments, the fluff in the codex says more than enough to know the answers to your questions.
In short there are 2 ways to deal with the power from pain over long periods of time:
1)You become more and more powerful, you try to become an archon or a highly placed kabalite/wych, to have access to plenty of slaves and souls to consume
2)you become a heamonculi, there are two sides to being a heamonculi: first;you can apparently feed yourself on your own suffering as well as that of others. Wracks are the first step, like said in the codex, they let a heamonculi mutilate them and apparantly enjoy it it and take it willingly.
On the other side what they learn from their masters is how to get more suffering from their victims, this is the advanced method to survive the power from pain. learning how to properly torture a victim takes time, that's the real training wracks need to go through to become a heamonculi.
Young dark eldar don't need that much suffering to survive, but it gets worse with time, when you get really old, you start noticing it.
Both Heamonculi and Kabalites/wyches are actually similar, they have the same ambitions, they just take different paths. Kabalites and wyches are both warrior types purely relying on their strength, numbers and weapons, wyches just prioritise the fighting while kabalites prioritise the rise to power, though they are certainly great warriors.
There's actually a another way to deal with the power from pain, now this one is a true mystery, very, but very little is known about these guys: the Mandrakes. They are still dark eldar, or at least used to be, but things changed drasticly to the point where they can use the power from pain to shoot flames (something other dakr eldar clearly can't do XD) Now how is this achieved,why, etc... that's a mystery, but it's clear that mandrakes are very different from other dark eldar, they have no great ambitions, no big armies, no machines, it's not even clear what they truly want.
The flames aren't the only major difference, appearance and the fact that they can travel using shadows is also a major difference.
There's a whole thread about this in this background section if you're interested on theories on mandrakes.