Bzzzt!
The screen went black. Mortarion froze for a moment before realizing that Jaghatai had simply hung up on him.
"How dare you! How dare you treat me like this?!" Jaghatai's disdain enraged Mortarion. Black smoke and poisonous mist poured from his armor. He viciously slammed the fungus-covered console twice, then ordered his men to reconnect him to Jaghatai.
The screen lit up again. Mortarion quickly composed himself and put on an act as though Jaghatai's discourtesy had not bothered him in the slightest.
"Jaghatai, isn't it terribly rude to treat your brother this way? Don't you pride yourself on being civilized? Yet you can't even—"
"Didn't I say not to put his calls through? Who did this? You, right? Forget about getting paid this month. Looking at him makes me sick. How am I supposed to eat dinner tonight?"
The screen went black again. In the final second before the connection cut off, Mortarion heard Jaghatai's complaint.
Mortarion stood there blankly for a long while. Though he said nothing, even more poisonous gas poured from his armor. The spore- and tumor-covered flesh on his back also began bubbling like it was boiling.
"Primarch, we..." a Death Guard soldier timidly reminded him. Mortarion immediately erupted, pounding the console again as he ordered his men in an even harsher tone to contact Jaghatai.
After a long time of trying, the screen still would not light up. Jaghatai had completely blocked Mortarion's communications. Filled with rage, Mortarion refused to give up. He brought out the cauldron used for rituals, intending to contact Jaghatai through sorcery.
Several tiny bone fragments floated atop the greenish broth. As Mortarion stirred it, the bones assembled themselves into words before dissolving back into the soup and vanishing.
"Jaghatai!!! I'll kill you!"
A cluster of spores inexplicably sprouted