11. Arena Tier

function arenaArena(input) {
  function Gladiator(name = '', technique = '', skill = 0) {
    this.setTechnique = (technique = '', skill = 0) => {
      if (this.tech[technique] === undefined || this.tech[technique] < skill) {
        this.tech[technique] = skill;
      }
    };

    this.getTotalSkill = () => Object.values(this.tech).reduce((total, skill) => total + skill, 0);

    [this.name, this.tech] = [name, {}];
    this.setTechnique(technique, skill);
  }

  function Arena() {
    this.addGladiator = (name = '', technique = '', skill = '') => {
      const gladiator = this.gladiators[name];
      if (!gladiator) {
        this.gladiators[name] = new Gladiator(name, technique, Number(skill));
      } else {
        gladiator.setTechnique(technique, Number(skill));
      }
    };

    this.battle = (gladiator1Name, gladiator2Name) => {
      const [gladiator1, gladiator2] = [this.gladiators[gladiator1Name], this.gladiators[gladiator2Name]];
      if (!gladiator1 || !gladiator2) {
        return;
      }

      const alltech = Object.keys(gladiator1.tech).concat(Object.keys(gladiator2.tech));
      if (alltech.length !== new Set(alltech).size) {
        const loser = gladiator1.getTotalSkill() > gladiator2.getTotalSkill() ? gladiator2.name : gladiator1.name;
        delete this.gladiators[loser];
      }
    };

    this.executeCommand = (line = '') => {
      line.includes('->') ? this.addGladiator(...line.split(' -> ')) : this.battle(...line.split(' vs '));
    };

    this.gladiatorsInfo = () => Object.values(this.gladiators)
      .sort((a, b) => b.getTotalSkill() - a.getTotalSkill() || a.name.localeCompare(b.name))
      .map((gladiator) => {
        const tech = Object.entries(gladiator.tech)
          .sort(([tech1, skill1], [tech2, skill2]) => skill2 - skill1 || tech1 - tech2)
          .map(([technique, skill]) => `- ${technique} <!> ${skill}`)
          .join('\n');
        return `${gladiator.name}: ${gladiator.getTotalSkill()} skill\n${tech}`;
      })
      .join('\n');

    this.gladiators = {};
  }

  const tier = new Arena();

  let line = input.shift();

  while (line !== 'Ave Cesar') {
    tier.executeCommand(line);
    line = input.shift();
  }

  return tier.gladiatorsInfo();
}