Masters of the Universe

Masters of the Universe is a science fantasy media franchise created by Mattel. It began with a television series and toy line about a superhero named He-Man and his conflict with Skeletor.
There have been a total of seven animated series, several comic series, video games and books and two movies.
Setting
The story is a hybrid setting of science fiction (such as advanced technology, spaceships and robots) and medieval aspects (such as swords and magic).
On Eternia, there is a fortress called Castle Grayskull and it contains secrets about how to become a Master of the Universe. The Castle is protected by a good witch called the Sorceress. The main character of the story is He-Man, a muscular superhero who wields a magical sword. He is fighting against Skeletor.
Story
The main premise of Masters of the Universe is the conflict between He-Man and Skeletor. Skeletor is an evil wizard who wants to conquer Eternia and get the powers and secrets from the mytserious fortress called Castle Grayskull. Both characters have their allies who help them. In addition, there are spin-off shows about She-Ra, the sister of He-Man, and her adventures.
Timeline
Each television show has details about events and characters that differ from the other shows. For this reason, they are not all in the same timeline. However, there have been some attempts to form a timeline between a few of the material. The "main timeline" is often considered to be: the 1983 series, The Secret of the Sword, She-Ra: Princess of Power and Revelation.
Main characters
He-Man
He-Man is the main protagonist of the Masters of the Universe franchise. He is a strong, muscular superhero whose mission is to protect Eternia and Castle Grayskull from the series' main villain, Skeletor.
He-Man is known for his strength and for wielding a magical sword called the Power Sword. He also has a famous line which he says whenever he takes out his sword: "I have the power".
In several variations of the story, He-Man's true identity is Prince Adam, the son of King Randor and Queen Marlena, the rulers of Eternia. Later in the franchise, He-Man's sister, Princess Adora is revealed.
He-Man is sometimes viewed as a gay icon. He has appeared in most of the franchise's media. He was voiced by John Erwin in the original 1983 series, the 1985 She-Ra spin-off, The Secret of the Sword film and several other specials.
In the 1986 live action movie, he is portrayed by Dolph Lundgren. In the 1989 series, he is voiced by Gary Chalk while Doug Parker provided the voice for He-Man's true identity, Prince Adam. In the 2002 series, He-Man is voiced by Cam Clarke. In Revelations, he is voiced by Chris Wood. In the 2021 3D animated series, He-Man's voice is provided by Yuri Lowenthal.
Skeletor
Skeletor is the main antagonist of the franchise. He is an evil skeletal demon and wizard who wants to take over Eternia and become the Master of the Universe. Skeletor is the leader of a group mostly known as the Evil Warriors, which includes his many underlings.
Skeletor was first portrayed as a simple evil supervillain. In later versions of the story. it is revealed that Hordak (another major villain) was Skeletor's teacher. It is also hinted many times that Skeletor is actually Keldor, the brother of He-Man's father, King Randor.
Alan Oppenheimer provided the voice of Skeletor in the 1983 original series, the 1985 She-Ra series and all related material to the two shows, including The Secret of the Sword animated film. In the 1986 live action movie, he is portrayed by Frank Langella. In the 1989 series, he is voiced by Campbell Lane. Brian Dobson provided Skeletor's voice in the 2002 series. In Revelation, he is voiced by Mark Hamill. In the 2021 series, Ben Diskin voiced the character.
She-Ra
She-Ra is a major character and the protagonist of two spin-off shows: She-Ra: Princess of Power and She-Ra and the Princesses of Power.
Her true identity is Princess Adora and she is the sister of He-Man. In her spin-off shows, she battles to defend the planet Etheria from Hordak and the Evil Horde.
She-Ra was introduced in The Secret of the Sword, where she was voiced by Melendy Britt, who also voiced her in She-Ra: Princess of Power. In the new reboot, She-Ra and the Princesses of Power, she is voiced by Aimee Carrero.
Others
The Sorceress is a good witch who protects Castle Grayskull.
Man-At-Arms is a loyal soldier who is one of He-Man's most important allies.
Teela is the daughter of Man-At-Arms. She is the captain of the Eternian Royal Guards. Teela is often presented as a love interest of He-Man.
Orko is a short alien magician who floats around and has his face concealed behind his robes and hat.
Cringer is He-Man's green pet tiger who transforms into a mighty beast called the Battle-Cat.
Evil-Lyn is a wicked sorceress and is one of Skeletor's most feared underlings.
Hordak is the main antagonist of the She-Ra spin-off series. He is the leader of the Evil Horde (which includes a wide group of villains) and tries to conquer the planet Etheria.
King Randor and Queen Marlena are the parents of He-Man and She-Ra and the rulers of Eternia.
The Evil Warriors are a group of aliens who work for Skeletor and Evil-Lyn. They include: Beast-Man, Mer-Man, Trap Jaw and Tri-Klops.
The Great Rebellion includes a group of characters in the She-Ra spin-off series including Bow, Kowl, Madame Razz, Broom and Queen Angella.
Media
The franchise consists of many toy lines, comic series, video games, movies and television shows. He-Man first appeared in a 1982 comic.
Television series
All television series do not appear occur in the same timeline because many details change. However, Revelation is a sequel of the first He-Man and She-Ra series.