Lancelot

Birth
Lancelot was born in Avalon to Vivian and the King of France, though his father quickly left to tend to his kingdom. Being born and raised in Avalon, he absorbed extreme amounts of energy, with his body essentially becoming a holy sword similar to Caliburn or Excalibur. After spending his childhood and teen years there, he headed to Camelot to become a knight.

Arthur
Upon arriving at Camelot, Arthur and Lancelot ended up having a fight, where Lancelot overpowered Caliburn with a stick off the ground. Afterwards, he fell in love with Arthur and the two were married. He proceeded to get married to each of the other knights of the Round Table, as each of them had. He eventually went on to destroy Caliburn in training a week before Britain went to war with Europe.

Adventures of the Round Table
Throughout Britain's war with the rest of Europe and against mythical beasts, Lancelot remained by far the most powerful knight of the Round Table, only matched by Excalibur's full power. At some point, he had a son named Galahad, and raised him, giving him the blessings of Avalon to become even more powerful than Lancelot.

Fall of Camelot
When Arthur was called away by the actions of Morgan, Agravain and Mordred betrayed the rest of the knights when they began attacking the Round Table. Due to Lancelot being from Avalon, and his body being a Holy Sword, his body was instantly destroyed when he was struck by Agravain wielding Clarent. Due to the nature of Clarent, it was possible for him to be alive in Avalon after Ten Beard destroyed Clarent.

Moon Wars
During the Moon Wars, Lancelot returns from Avalon to fight against Morgan, and later fights against Ardon in training.