Very much true, on the otherhand it was very much touch and go what would be allowed to the fold of the imperium and what not. Psykers = Eradicate, Mutants = Eradicate, Usage of advanced AI = Eradicate, Living along xenos = Eradicate, Too stubborn to surrender after the initial show of force = Eradicate as an example of what happens when you dont surrender. All sanctioned By the emperors will and "normal". All legions did it as it was just the way of doing business. World eaters were actually pretty effective as the lore tells many mutinous worlds would surrender just because world eater ships were spotted. We are afterall talking about a world where killing a million people is all in a days work.
Not really true. The Thousand Sons were infamous for using diplomacy as often as force, and for conserving much of the existing cultures that they 'conquered' during the Great Crusade. They are the extreme example, but it goes to show that methodology was largely left up to the primarchs. Guilliman and Magnus were more civilization builders than conquerors, and it showed. Russ, Fulgrim, and Angron chose to interpret the Emperor's directives in the most bloody way possible.
Did some of the Primarchs have a good reason to rebel? Yes. Did they find the correct way to do it? Heck no. Leaving the rule of a "tyrant" to be under the rule of Gods that revel in mindless slaughter or that take pleasure in the form of every kind of pain, perversity and degradation known to man kind of seems like the wrong path to take when you're a Primarch with daddy issues and you feel wronged. Yes some Primarchs were mistreated, but calling the Emperor evil is a joke compared to what the Primarchs turned into during/after the rebellion.
To be fair, Horus only rebelled due to the chaplain Erebus/the Word Bearers turning to chaos and then subsequently turning him (Horus) to Chaos, so his "reasons" was more that he was already corrupted into the Chaos god's plans.
Am I the only one who thought that part was a bit disappointing in the books? Horus was a great and wise primarch prior to that event and then suddenly turns completely crazy and starts murdering everyone. I think I was expecting a slower degree of changer, less noticeable for everyone which takes smaller steps until the heresy itself. But the way it was presented, it seemed like someone completely replaced Horus with another person in the midst of a story.
Well the Word Bearers themselves have their justification based on Chaos being the realization of their religious beliefs, while Horus himself really lacks justification being that he was essentially manipulated to be the leader of the rebellion. And I'll have to agree with the hamster, it's not that good of storytelling for it to have been so sudden of a personality change. Really it should be a slow progression into madness.
Indeed I like how they showed Konrad Curze/Night Haunter dwelving into his insanity going from being the terror that brought up justice and punished deplorable acts transforming into what he despised along with his legion it seemed like in his story the Night Haunter was the prodeminant personality at the end of his days
