Chosen Hero

Hero (勇者) refers to the counter-part of Demon Lords, an existence that only those who have the blessing of an Elemental of either Light or Darkness can obtain.

As is the case with Demon Lords, Heroes can be divided into those who are known as Hero in title or those who are Heroes as a "Class" as well as those who are neither or both.

Hero's Egg
Hero's Egg (勇者の卵) refers to those who obtain the blessing of an Elemental of Light or Darkness as well as the Spirit Queen. The Hero's Egg is the equivalent of the Demon Lord Seed.

True Hero
True Heroes (真なる勇者) or The One who hatched the Hero's Egg (勇者の卵が孵った者), are those who hatched a Hero's Egg and became an awakened Hero. It is one of the ultimate forms of existence that Humans and Demi-Humans can attain. Awakened/True Hero is the equivalent of an Awakened/True Demon Lord.

Hero as a Title
Anyone can proclaim themselves a Hero, or be recognized by the masses as a Hero. In either case this "puts fate into motion" and causes this Hero by title to eventually have some sort of predestined connection with a Demon Lord that is unavoidable, though it does not necessarily have to be a hostile relationship.

Hero's Path

Hero's path is hard and strict. Theoretical any Human or Demi-Humans(which closer to humans then to monsters like elves, dwarfs, halflings) can become a True Hero but not everybody of them enough strength, willpower, luck and hero's qualities. But even if you become a True Hero you must continue to be worthy of this title if you don't want to lose it.

Rising

Hero's Path has 3 phase Blessing, Egg, Awakening.

1) Blessing - Those who want become a hero must go to the Dwelling of Spirits and obtain the blessing of an Elemental of Light or Darkness(Divine Protection of the Light Spirit from Elemental of Light or Divine Protection of the Dark Spirit from Elemental of Dark(must have one of them don't matter which one)) as well as the Elemental Queen(unnamed Divine Protection from Spirit Queen Lamrys). It's sounds easy but Great Elementals of Darkness and Light are very rare and capricious which makes them difficult to find and get their favour. It's all depends on luck but chances will be higher if candidate is a good person and has good disposition towards the light or darkness. After receiving all blessing the candidate take a oath to protect mankind.

2) Egg - Candidate get his Hero Egg when she/he make a lot of good deeds(sincerely) and become strong enough at least Calamity level. When candidate obtain a Hero Egg she/he will be known as Hero's Egg and get official title Hero.

3) Awakening - Candidate must "hatch" his Hero Egg to awaken as a True Hero. Hero Egg will "hatch" when hero willpower and will to save mankind will be strong enough and when a hero will be ready to take responsibility for mankind and his title.

Properties
True Heroes

Awakened/True Heroes in a terms of strength are on par with Awakened/True demon lords. Power level of "average" True Heroes (Hinata, Granbell) varies from highest Disaster to low Catastrophe rank but the most powerful among them (Rudra, Chloe) can fight on equal terms even with True Dragons. True Heroes possess an incredible willpower, a soul (which is powerful enough to have an Ultimate Skill and reincarnate without consequences) and extremely long lifespan. They can achieve divinity which will make them stronger and free them from mortality. Evil, unprincipled can't become a True Heroes. Heroes usually have a nice personality(Chloe, Rudra), when some of them have more rude and cruel personality(Hinata, Granbell) but each and all Awakened Heroes must have desire to help people and protect mankind.

Hero's Egg

Hero's Eggs usually wield power equal to demon lord seed, from hight Calamity to low Disaster but their strength can be higher from medium Disaster to high Disaster if Hero's Egg is saint as well. Completely saints with Hero Egg can give a fight even to a True Demon Lord but chances to win not be very hight to put it mildly. They also have Divine Protection from spirits that help them in fight. Evil, unprincipled can't become a Hero's Egg. Hero's Eggs usually have a nice (Chloe, Rudra, Sarion), when some of them have more rude and cruel personality(Hinata, Granbell) but each and all Hero's Eggs must have desire to help people and protect mankind.

Champions/Proclaiming Heroes

Champion's level of strength is varies greatly from low Hazard to high Disaster. Also they loved by the people who admit them as heroes. They usually have noble personality.

True Heroes

 * Masayuki Rudra Nam Ul Nasca
 * Granbell Rosso (Formerly)
 * Chloe Aubert
 * Leon Cromwell (Formerly)
 * Hinata Sakaguchi
 * Granit

Hero's Eggs

 * Sarion Grimwald (Formerly)
 * Granbell Rosso (Formerly)
 * Leon Cromwell (Formerly)
 * Masayuki Rudra Nam Ul Nasca (Formerly)
 * Hinata Sakaguchi (Formerly)

Champions/Proclaiming Heroes

 * Youm Farmenas
 * Gazel Dwargo
 * Shizu
 * Seven Luminaries

Trivia

 * In the English translations Hero (勇者) is often mixed up with Champion (英雄) because both these terms are usually translated as "Hero" out-of-context. This has sometimes caused "Champions" in the English translation of the series to be mixed up with Heroes. Likewise the term Heroic King (英雄王) also refers to Champions and not Heroes.

Reference
pt-br:Herói Герой