The Red Priest is the pinnacle of the path of war, fire, and conspiracy.
The ascension ritual continues the same straight line that led from hunter to conqueror: to unleash a war spanning an entire continent and achieve sufficient victories within it. Not to win a single battle — but precisely to wage war of such scale and to prevail.
From the ritual ingredients, canon names one position, and it is unusual: a deep projection of one's own state into the Mirror World. To ascend, one needs neither a substance nor a creature, but a country — and, moreover, its reflection on the other side of the mirror.
The potion is described as a crimson pillar shrouded in formless flame, and the characteristic — as a bloodstained iron-black shaft with a banner. The symbol is chosen precisely: the path ends not with a crown and not with a throne, but with a banner around which they gather.