gistfile1.js

Entity = function (name, stats) {
    
    this.ui = {
        healthBar: $('<div id="healthBar" class="progress-bar progress-bar-danger"></div>')
        manaBar: $('<div id="healthBar" class="progress-bar progress-bar-danger"></div>')
    };

    // Append UI
    $('body').append(this.ui.healthBar);
    $('body').append(this.ui.manaBar);

    this.name = name;
    this.stats = _.extend({
      health    : 100,
      maxhealth : 100,
      mana      : 100,
      maxmana   : 100,
      timer     : 3000,
      maxtimer  : 3000,
      PP        : 10,
      MP        : 10,
      defense   : 10,
      accuracy  : 10,
      gold      : 100,
      exp       : 0,
      maxexp    : 10,
      level     : 1,
      statpoints: 5
    }, stats)
  };
};

Entity.prototype.attack = function (target) {
  target.stats.health -= this.stats.PP;
  return target;
}

// Update UI

Entity.prototype.updateUI = function() {
    this.ui.healthBar.css({'width' : Math.floor((this.stats.timer/this.stats.maxtimer)*100) + '%'});
    // etc..
}

var enemy1 = new Entity('goblin', {
    maxtimer: 3750,
    timer: 3750
});