multiple inheritance in js

captain.js

function Entity() {
}

Entity.prototype.entityThing = function() {
  console.log("entity thing");
};

function NPC(name) {
  Entity.call(this);
  this.name = name;
}

NPC.prototype = Object.create(Entity.prototype);
NPC.prototype.constructor = NPC;

function Captain(name, hp) {
  NPC.call(this, name);
  this.hp = hp;
}

Captain.prototype = Object.create(NPC.prototype);
Captain.prototype.constructor = Captain;

Captain.prototype.captainSlashOfFury = function() {
  console.log("I am Captain " + this.name + " and I have " + this.hp + " left!");
  console.log("Slash slash slash!!!!");
};

var brian = new Captain("Brian", 100);
brian.entityThing();
brian.captainSlashOfFury();