Halarus wasn’t a warrior.
He wasn’t even a true wizard.
The man was a quivering reservoir of public decrees and order. A man of law and pageantry. He learned to read from his father, a scholar, and was urged by his mother for greater things through true understanding of their people.
Tzeentch does not necessarily care about what people know or do not know, Tzeentch simply cares for the growth of their power, and of course mighty change.
Halarus’ mind was already bent before the Chaos corruption seeped through his lands, and it bent further still as he saw his friends and family shift and fall apart around him.
Halarus was not killed at this time; he knew too much about state affairs, about advising and ruling. He served his own warped family and people for far too long. Halarus longed for death, for what his people and lands had become was worse than seeing it be slaughtered… and he was serving the very thing he was intent on opposing.
His closest friend eventually killed him. Impaled through the chest by a flaming weapon of blue fire, mind-melding overflowing with memories he was no longer sure were his, his father’s, mother’s, or some daemons thoughts implanted onto him.
As he fell down a chasm, dying, wailing, a light overwhelmed him, stealing him, and he was purified. Purified in death by an Azyrian energy.
Sigmar saves, but only those he can.
Heartsburn. Halarus Heartsburn. Reforged at the hammer and Anvil of the Apotheosis. As the man’s vision cleared and the pain faded, mind racing with thoughts, a younger woman reached for his hand, no longer malformed, but whole and his. The young woman’s deep green eyes were focusing on his, she bore short, braided blonde hair and a tender smile.
His Knight-Incantor, his eventual ally, and friend.
They may not have known each other in life as mortals, but she was practically the only thing that held him together in Azyr. Study, trust, training, and purpose began to put Heartsburn’s mind on track again. Decades, centuries of work. And even then he was not who he was before Tzeentch. His mind spoke out without his permission, his thoughts on display for anyone close enough. It was a curse, but, sometimes, a blessing also… he could never lie, he could never withhold his thoughts, ill or optimistic, but the winds of magic came to him easier too, in such flashes of inspiration he amazed even the greatest of wizards in Azyr.
Halarus Heartsburn, Lord-Arcanum, and agent of Sigmar in the crusade against Chaos in Shyish. His mind flooded with heavenly light and magic, protector of souls and his fellow Stormcast.
Given supplies, some soldiers, and the encouragement of his Knight-Incantor, Oleandra, he’ll begin his Stormhost’s entrance into the untamed lands of the fringes of Shyish, rumors of a great power rose there and if proven true, he’ll be the first foothold there against any threat opposed to Order.
