Game_BattlerBase.prototype.paySkillCost = function (skill) {
  var bloodMagicItems = [];
  if (this.isActor()) {
    bloodMagicItems = this.equips().filter(function (equip) {
      if (!equip) { return; }
      return equip.note.indexOf('<BloodMagic>') !== -1
    });
  }

  if (bloodMagicItems.length || skill.note.indexOf('<BloodMagic>') !== -1) {
    this._hp -= this.skillMpCost(skill);
  } else {
    this._mp -= this.skillMpCost(skill);
  }
  this._tp -= this.skillTpCost(skill);
};

Game_BattlerBase.prototype.canPaySkillCost = function (skill) {
  var bloodMagicItems = [];
  if (this.isActor()) {
    bloodMagicItems = this.equips().filter(function (equip) {
      if (!equip) { return; }
      return equip.note.indexOf('<BloodMagic>') !== -1
    });
  }

  if (bloodMagicItems.length || skill.note.indexOf('<BloodMagic>') !== -1) {
    return this._hp >= this.skillMpCost(skill);
  } else {
    return this._tp >= this.skillTpCost(skill) && this._mp >= this.skillMpCost(skill);
  }
};