Emperor's light. 

It was every inquisitor's knowledge that chaos was utterly enthralling if one was to delve too deep into its clutches, but this was another level of coercion entirely. To compel anyone to serve after merely reading from a scroll, it must have been enchanted powerfully. But to what end? There had to be a concrete goal to the heretics, utilizing this compulsion for some aim beyond just spreading corruption. I shook my head, dabbing the blood from Emmaline's lip with a cloth. Her blue eyes were wide, but by the Emperor's Mercy I saw the same woman I loved still in there. 

"Hadrian, they can enslave millions of people." She repeated, clearly stating it again so she could also come to terms with the visions that had bombarded her mind. Her slim fingers clutched my jacket.

"Potentially, but even chaos has limits." I said, considering. I looked to the left as I pondered, mind whirring like the cogs in a mechanicus cogitator. "If they could simply read the words and force someone into servitude, they would have done that to you, or worse, they would have tried to broadcast the message across the lower hive. They also cannot print it on any piece of parchment, or it would easily be mass produced. No, there are only a specific number of these scrolls with the spells of compulsion writ upon them." 

"So one needs to read it for themselves in order to be influenced," Emmaline remarked, holding her head as she shook off the aftershock of the assault on her mind. 

"Which means they cannot enslave the entirety of a hive without special circumstances or equipment." I said. 

"Like a holovid?" Emmaline asked, hopeful she was correct but equally yearning to be wrong. "Where would they have access...?" 

"We're going to the upper hive." I said.