I'm not going to kill them for weeks. Instead I will first cripple them and send out a massive message throughout the world that he is dead so that there will be no people attempting to save him. He will be kept in a small room where he will be well fed, and medicated as we slowly punish him. Some days it will be severe others there will be nothing. I want him to spend his time thinking about why he shouldn't have opposed me, and the unpredictability should kill him. Afterward I will grow tired of that and instead put subtleties in my speech that creates thoughts of freedom. I'll do plenty of other things, but I"m not getting into details. Then after weeks of this I will present him the ability to kill himself, while telling him reasons to want to live, and I'll see how long it takes for his mind to snap.
To take over the world? That's a secret.