<p>Open developer console to see output</p>
class Animal {
  constructor(noise) {
    this.noise = noise;
  }

  eat() {
    console.log("Om nom nom");
  }

  sleep() {
    console.log("Zzzzzzz");
  }

  makeNoise() {
    console.log(this.noise);
  }
}

class Pig extends Animal {
  constructor() {
    super("Oink!");
  }

  wallowInMud() {
    console.log("Aaaahh...");
  }
}

class Horse extends Animal {
  constructor() {
    super("Neigh!");
  }

  prance() {
    console.log("Eeek!!");
  }
}

class Human extends Animal {
  constructor() {
    super("Cogito ergo sum.");
  }

  inventFire() {
    console.log("Ow, that's hot!");
  }
}

class Bird extends Animal {
  constructor(noise, canFly = true) {
    super(noise);
    this.canFly = canFly;
  }

  fly() {
    if (this.canFly) {
      console.log("I'm flyyyying");
    } else {
      console.log("I can't fly, you fools!");
    }
  }

  layEgg() {
    console.log("*Plop*");
  }
}

class Owl extends Bird {
  constructor() {
    super("Hoot");
  }
}

class Kiwi extends Bird {
  constructor() {
    super("Shriek!", false);
  }
}

const pig = new Pig();
const horse = new Horse();
const human = new Human();
const owl = new Owl();
const kiwi = new Kiwi();
pig.makeNoise();
pig.wallowInMud();
horse.makeNoise();
horse.prance();
human.makeNoise();
human.inventFire();
owl.makeNoise();
owl.layEgg();
owl.fly();
kiwi.makeNoise();
kiwi.layEgg();
kiwi.fly();

console.log(pig, horse, human);
console.log(owl, kiwi);
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