es615.js

class Lannister {
  dieNext() {
    const victim = [
      'Tyrion',
      'Cersei',
      'Jamie'
    ];
    console.log(`${this.name} is going to kill ${victim[Math.floor(Math.random() * victim.length)]}!`);
  }
  constructor(data) {
    this.name = data.name;
    this.father = data.father;
    this.hairColor = data.hairColor;
  }
}

let Joffrey = new Lannister({ name: 'Joffrey', father: 'Jamie' });
Joffrey.dieNext(); //Joffrey is going to kill Jamie! 😱