From "Manual of Muad'Dib" by the Princess Irulan

Those two, eh? the Baron thought. Ah, this young monster has much to learn yet about conspiracy!
"I presume you left matters peaceful in the slave quarters, Feyd," the Baron said.
"I've been playing cheops with the slavemaster," Feyd-Rautha said, and he thought: What has gone wrong? The boy we sent to my uncle has obviously been killed. But he was perfect for the job. Even Hawat couldn't have made a better choice. The boy was perfect!
"Playing pyramid chess," the Baron said. "How nice. Did you win?"
"I . . . ah, yes, Uncle." And Feyd-Rautha strove to contain his disquiet.
The Baron snapped his fingers. " Nefud , you wish to be restored to my good graces?"
"Sire, what have I done?" Nefud quavered.
"That's unimportant now," the Baron said. "Feyd has beaten the slavemaster at cheops. Did you hear that?"
"Yes . . . Sire."
"I wish you to take three men and go to the slavemaster," the Baron said. "Garrote the slavemaster. Bring his body to me when you've finished that I may see it was done properly. We cannot have such inept chess players in our employ."
Feyd-Rautha went pale, took a step forward. "But, Uncle, I—"
"Later, Feyd," the Baron said, and waved a hand. "Later."
The two guards who had gone to the Baron's quarters for the slave boy's body staggered past the antechamber door with their load sagging between them, arms trailing. The Baron watched until they were out of sight.
Nefud stepped up beside the Baron. "You wish me to kill the slavemaster, now, my Lord?"
"Now," the Baron said. "And when you've finished, add those two who just passed to your list. I don't like the way they carried that body. One should do such things neatly. I'll wish to see their carcasses, too."
Nefud said, "My Lord, is it anything that I've—"
"Do as your master has ordered," Feyd-Rautha said. And he thought: All I can hope for now is to save my own skin .
Good! the Baron thought. He yet knows how to cut his losses . And the Baron smiled inwardly at himself, thinking: The lad knows, too, what will please me and be most apt to stay my wrath from falling on him. He knows I must preserve him. Who else do I have who could take the reins I must leave someday? I have no other as capable. But he must learn! And I must preserve myself while he's learning .
Nefud signaled men to assist him, led them out the door.
"Would you accompany me to my chambers, Feyd?" the Baron asked.
"I am yours to command," Feyd-Rautha said. He bowed, thinking: I'm caught .
"After you," the Baron said, and he gestured to the door.
Feyd-Rautha indicated his fear by only the barest hesitation. Have I failed utterly? he asked himself. Will he slip a poisoned blade into my back . . . slowly, through the shield? Does he have an alternative successor?
Let him experience this moment of terror , the Baron thought as he walked along behind his nephew. He will succeed me, but at a time of my choosing. I'll not have him throwing away what I've built!
Feyd-Rautha tried not to walk too swiftly. He felt the skin crawling on his back as though his body itself wondered when the blow could come. His muscles alternately tensed and relaxed.
"Have you heard the latest word from Arrakis?" the Baron asked.
"No, Uncle."
Feyd-Rautha forced himself not to look back. He turned down the hall out of the servants' wing.
"They've a new prophet or religious leader of some kind among the Fremen," the Baron said. "They call him Muad'Dib. Very funny, really. It means 'the Mouse'. I've told Rabban to let them have their religion. It'll keep them occupied."
"That's very interesting, Uncle," Feyd-Rautha said. He turned into the private corridor to his uncle's quarters, wondering: Why does he talk about religion? Is it some subtle hint to me?
"Yes, isn't it?" the Baron said.
They came into the Baron's apartments through the reception salon to the bedchamber. Subtle signs of a struggle greeted them here—a suspensor lamp displaced, a bedcushion on the floor, a soother-reel spilled open across a bedstand.
"It was a clever plan," the Baron said. He kept his body shield tuned to maximum, stopped, facing his nephew. "But not clever enough. Tell me, Feyd, why didn't you strike me down yourself? You've had opportunity enough."
Feyd-Rautha found a suspensor chair, accomplished a mental shrug as he sat down in it without being asked.