Later, Mohiam accompanies Emperor Shaddam IV to Arrakis in her role as Imperial Truthsayer; there she is faced with Paul's four-year-old sister, the pre-born Alia, whom she calls an Abomination. Mohiam is further alarmed as she witnesses the ritual battle-to-the-death between Paul and Feyd-Rautha. Paul calls Feyd "cousin," revealing that Paul is aware of the secret that the Baron Harkonnen is his grandfather. But Mohiam is most concerned with the potential outcome of the duel, which could prove to be "a major catastrophe for the Bene Gesserit breeding scheme." She realizes that "Two end products of this long and costly program faced each other in a fight to the death that might easily claim both of them. If both died here that would leave only Feyd-Rautha's bastard daughter, still a baby, an unknown, an unmeasured factor, and Alia, the Abomination."