These are my own bios that I created. I try and stay true to the original mythos, but with adding my own ideas and few changes (i.e. real names, monikers etc.). I hope you like them. More will be coming...

He-Man
Strongest Man in the Universe
Real Name: Prince Adam


On his 16th birthday, Prince Adam's life changed forever. Being depicted as the stereotypcial "spoiled brat", Adam changed his ways when he was taken to Castle Grayskull and was told he was destined to become He-Man, the strongest man in the universe. Witnessing the destruction and evil of his future arch nemesis Skeletor, he seized his destiny and became He-Man, the ultimate savior of Eternia. Alongside his heroic Masters of the Universe, He-Man is dedicated to protecting Castle Grayskull, all of Eternia and the entire universe.

Skeletor
Overlord of Destruction
Real Name: Prince Keldor of Eternia


After being banished from Eternos City, Keldor wandered Eternia as a dabbling alchemist. When he hungered for power, he attacked the Council of Elders. His plans were thwarted as his brother Captain Randor arrived and mortally wounded him in battle. Seeking help from his master Hordak, the ruthless leader of the Evil Horde merged Keldor's body with the evil spirit of Demo-Man, transforming him into the diabolical Skeletor, Lord of Destruction. Skeletor only has two goals - the fall of He-Man and universal conquest.

Sorceress
Mysterious Protector of Grayskull
Real Name: Teela'Na


A simple farm girl who wanted to save her village from otherwordly invaders, Teela'Na left her hometown in search for help. She came across the mysterious Castle Grayskull, where she was greeted by its defender, the sorceress Koduk Ungol. The Sorceress told her that she was a woman of courage, compassion and inner strength, making her the next chosen protector of Grayskull. Given insurmountable magic powers and everlasting life, the Sorceress saved her homeland and took her place as the defender of Grayskull, waiting for the arrival of the Twins of Power.

Evil-Lyn
Evil Warrior Witch
Real Name: Evelyn Powers


With no memory of her past and childhood, Evelyn became a maid in the royal household in her late teen years. She fell in love with Prince Adam, but Queen Marlena sensed evil in her and forbade the affair .After an attempt to kill the queen and steal Adam's love, Evelyn was exiled to the Dark Hemisphere by King Randor. There, she met Skeletor, who trained and transformed her into a terrible sorceress of unimaginable evil power. She serves Skeletor as his right-hand ally and most powerful cohort, wishing to one day destroy the Masters of the Universe and even Skeletor himself so she could rule Eternia herself.

Man-at-Arms
Heroic Master of Weapons & Technology
Real Name: Duncan W'ar


A legendary war hero, Man-at-Arms fought alongside King Randor during the Great Unrest. Due to his loyal service and legendary status, when Randor became King, he chose Duncan to become his royal advsior and bodyguard. Duncan served the King and Queen loyally for many years, raising his daughter Teela and even becoming a father figure and mentor for Prince Adam. Today, he commands the Masters of the Universe, creating all their magnificent weapons and vehicles, in their never-ending struggle against Evil.

Teela
Heroic Warrior Goddess
Real Name: Teelanas'sa


After the Sorceress was mortally wounded by the Unnamed One, her newborn daughter Teelana'sa was rescued by her life-long love, Duncan, a legendary war hero of Eternia. The Sorceress' magic was powerful enough to recover, but she knew that her daughter's life was at stake if the power of Grayskull ever fell into the wrong hands. Man-at-Arms adopted Teela, training her to be a fearless and mighty warrior. Teela grew up to be one of the greatest warriors in all Eternia, standing alongside her father and He-Man in their war for Eternia.

Battle Cat
Mighty Fighting Tiger
Real Name: Cringer


Cringer is a dwarf descendant of the legendary Green Tigers, who was found by Prince Adam when he was only a cub. Cringer found a home in Palace Eternia, but was teased for his fear and timidness. The Sorceress came to Adam and told him that Cringer will serve him well in the future. When Adam grew up and took on the mantle of He-Man, the power of Grayskull transformed Cringer into Battle Cat, a powerful warrior tiger who is a titan on the battlefield. Battle Cat serves He-Man as his loyal companion and is a valuable member of the Masters of the Universe.

Beast Man
Evil Master of Animals and Monsters
Real Name: Car'na'vurus


Keldor was almost killed by the sorcerer king Trinok in the Vine Jungle, but he was saved by the King of the Beast Men, Car'na'varus. Impressed by his animalistic savagery and monstrous strength, Keldor recruited Car'na'varus and the two became allies. Taking on the warrior name Beast Man, he possesses a remarkable special talent - he could telepathically control monsters and animals. Today, Beast Man serves the evil Skeletor as his most savage henchman, and uses his monstrous cohorts to terrorize Eternia.