code: function loadTowers() {
    const internalTowersInfo = getInternalTowersInfo();
    const externalTowersInfo = getExternalTowersInfo();
    return uniqBy(internalTowersInfo.concat(externalTowersInfo), 'id').map(
      ({ id, requirePath }) => {
        const { name, description, levels } = require(requirePath); // eslint-disable-line global-require, import/no-dynamic-require
        return new Tower(id, name, description, levels);
      },
    );
  }
docs: Loads the installed towers.
  
  @returns {Tower[]} The loaded towers.