Disclaimer: I own nothing of Warhammer 40K.

Perturabo

the Lord of Iron. Child prodigy

"it is a man's own mind, not his enemy or foe, that lures him to evil ways."

Never has there been a better quote to describe you.

From your first moments you understood the world around you. Others needed to be taught but you knew it all or so you believed you did. The answers were so obvious to you: if others didn't see that, then that was their failing. You couldn't learn that true leadership is raising those below you up rather than just giving orders.

So easy it must have been to grow cynical and mistrusting rather than attempt to understand, for the boy born with all the knowledge couldn't be bothered to learn from his believed "inferiors".

You believed that nobody wanted your dreams, just a tool even as some of your brothers grew beyond their home worlds. You could have learned from them but that would have been weakness to you.

Did it occur to you that you were given the worst tasks not because you were expendable but because you were valued?

Perhaps when the Emperor found you he saw a son with an unbreakable determination, one who would never give up, rise to best any task no matter the difficulty because he trusted no one else to complete the task.

You believed yourself to be the pawn when you were nothing of the sort. You could have spoken up, changed your legions battle doctrine to something else but you refused to do anything to better your situation. You accomplished tasks in the most painful way possible wanting others to notice your efforts, too arrogant to win people over, just expecting to be noticed. Your growth was halted by your inability to "take the next step' and so you never matured as a leader and a person.

The true tragedy of you?

There was a great hero underneath all your insecurity. You refused to seize power from your foster-father despite having the power, this act spoke greatly of you. Your dreams were of beautiful cities that you were not even the ruler but like all the traitor primarchs your inflexibility is your common curse.

Iron within, iron without.

There is no iron in you, merely a sullen boy squatting in the dreams you prevented from happening yourself.