Slush Head captures the Scientists of Primus as they are working on repairing the Trithuseum generators. Upon learning that they built the shield around Primus, Skeletor sends them to the Quagmi Swamp in Denebria. He-Man, Hydron, and Flipshot head to Denebria to rescue the Scientists and get them back to Primus to repair the Trithuseum generators before Primus' core overheats.

He-Man saves Grot's garden from an attack by Hoove and Karatti. Meeting Werban in the Oasis, Skeletor tricks him into lowering Onnor's shield of protection so that Hoove can lead the Evil Mutants to invade Onnor under the cover of a peace talk.

Following the failed attack on Onnor, Skeletor sends a hologram calling out He-Man to face him on the Cameroon Asteroid. While He-Man and Master Sebrian are sure it is a trap, He-Man goes anyway. While He-Man is facing off against Skeletor, Hoove and the Mutant Shuttle Pods attack Primus' main radar station while Crita, Lizorr, and Karatti capture Master Sebrian and Drissi.

Skeletor and Quakke find a crystal on Denebria that makes Quakke stronger. Quakke tests his new strength on He-Man, Hydron, and Flipshot during their trip to get oil for the Vasionic Resonator on Denebria and they are saved by Sagitar.

Obtaining a painting from a man named Helm, Skeletor and Slush Head stow away on Captain Tipper's ship and heads to a cave in Primus's wastelands and uses a spell to bring the dragon in the painting to life to cause chaos on Primus. He-Man, Hydron, and Flipshot then work to defend Primus from the dragon and other Temperic Oil paintings that Skeletor brings to life.

Master Sebrian and Adam get a message from the Galactic Council's leader that they will meet on the planet Enoos. The same message meets Skeletor and Flogg as they plan to sway the Galactic Council to their side even by having B.H. fake a hit on Mara that Skeletor will save her from. When this works and the Galactic Council suggests that both planets send delegations, He-Man, Hydron, and Flipshot head to Denebria where they are led into a trap by Slush Head and Lizorr while Skeletor and B.H. secretly have a plan to have an explosive ore burrow into Primus.

Drissi and Hydron doubt that Caz can join the Primus Space Force. As Flogg leads the Evil Mutants in the next attack, Skeletor and Quakke capture Caz when he tries to stop them and bring him to Denebria where Skeletor uses a special virus to keep him subdued. He will cure Caz of the virus if He-Man surrenders his Power Sword. He-Man comes up with a plan while taking Grot with him.

The Festival of Lights is a tradition where a solar eclipse happens to the Primian Suns and a celebration will occur after that where Caz states to Adam that they celebrate the return of the Suns. As He-Man will be attending an interstellar rodeo run by Buck Westar that comes to Primus, Skeletor plans to enter Primus by taking over Buck Westar's ship and capture the Galactic Guardians one by one until only He-Man and Sagitar are left.

At the advice of Skeletor, Flogg contacts Master Sebrian and gives Primus some Zeps as a goodwill gift for peace between Primus and Denebria. Once Primus is filled with Zeps, Skeletor and Flogg activate their remote that turns the Zeps into hideous beasts that attack the Primans. He-Man discovers that the Zeps are actually androids and that there are too many for him to fight all at once.

Primus has been taken over by the Evil Mutants and the Zeps. As He-Man and Mara have the key to the shield around Primus, Skeletor has captured Master Sebrian, Hydron, and Flipshot and sends B.H., Quakke, and Staghorn to find He-Man. Meanwhile, the Scientists of Primus work to find what makes the Zeps assume their monstrous forms.

At the advice of Flogg, Quakke puts up bounty posters for He-Man's capture as the Evil Mutants and the Zeps look for him. He-Man frees some prisoners from Slush Head as they join up in his resistance. When Skeletor threatens a village, He-Man offers to surrender if they spare the village.

As the Scientists of Primus work on a way to deactivate the Zeps, Adam and Mara go to where Master Sebrian, Hydron, and Flipshot are being held and free them despite interference by Crita, Slush Head, and the Mutant Troopers. Afterwards, He-Man and Master Sebrian provide a diversion for Skeletor while Mara, Hydron, and Flipshot retake the Starship Eternia.

Skeletor threatens to destroy Levitan if He-Man doesn't surrender. He-Man disguises himself as a Mutant Trooper to get close to Levitan while having a plan to retake Levitan and all of Primus with the help of the Galactic Guardians and the resistance. Though Skeletor will destroy Levitan anyway even if He-Man surrenders.

Tricking the Scientists of Primus with an award that will be presented at a space station, Skeletor and Flogg use a robot to have them decode the formula for Energon. This substance is used to melt and destroy planets and the award given to them is filled with it. The only thing that can destroy Energon is a power that is as evil as Energon.

The Evil Mutants have taken over the prison ship Gaolotia. When Caz and Drissi take an Astrosub and get baited to Gaolotia, Skeletor contacts He-Man telling him to come rescue them at Gaolotia. The Sorceress of Castle Grayskull contacts He-Man stating that Skeletor is having Gaolotia placed in the path of the comet Xenon.

After the Galactic Guardians capture Quakke and B.H., the Scientists of Primus create a machine called the Mutator that can turn any human into a mutant. When it is tested on He-Man so that he can spy on Skeletor, it changes more than his appearance as destroys the Mutator and rescues Quake and B.H. Not realizing that the mutant is a transformed He-Man, Skeletor names him Cruncher and takes him in storming the Inner Council's chambers.

A spaceship carrying a little girl arrives on Primus. He-Man and the Galactic Guardians are unaware that the little girl is actually a dangerous cyborg used by Skeletor in his plot to bring down the shield surrounding Primus.

The Galactic Guardians investigate a destroyed ship orbiting Primus and find a Hibernation Capsule containing Dukan who is one of the greatest heroes in Primus' past. Skeletor challenges Dukan to a duel in an abandoned city on Denebria. Suspecting trouble, He-Man, Hydron, and Flipshot secretly follow Dukan.

The Scientists of Primus create a Super Computer that would link all machines on Primus and the planetary shield. An exiled computer hacker named Mikros collaborates with Skeletor to place a computer virus called the Argazoid into the Super Computer. To combat the Argazoid, the Scientists of Primus use a shrink ray to shrink He-Man, Artilla, Gepple, and Alcon into the computer in order to keep Argazoid from reaching the Vasionic Resonator so that the Evil Mutants can invade.

Skeletor uses the Mind Lens to influence the human will. After causing damage on Primus, Skeletor wants to use the Mind Lens on He-Man.

Skeletor uses a brainwave detector to help him find He-Man. When Skeletor abducts a spaceship, He-Man is nowhere to be found.

Skeletor steals the plans for a gravity generator and builds one of his own. He plans to use it to push Primus out of its orbit where its temperature change threatens all life on Primus.

Using an image projector found on an asteroid, Skeletor disguises himself and the Evil Mutants as Professor Galactica's Interstellar Circus. They use this cover to kidnap the Scientists of Primus in order to have them work on the weapons found on the asteroid.

The Galactic Guardians destroy Flogg's new giant laser canon, but it's wreck emits a green gas that threatens the shield around the planet Primus. Skeletor soon produces more of the gas to weaken Primus and even He-Man's sword is affected.

Skeletor and Flogg have Primus' planetary shield bombed with everything they got. He places a special super-computer on a shuttle pod which He-Man obtains as the Scientists of Primus discover that it can produce clones. When the Scientists of Primus use it to clone the Inner Council members so that they can rest, Skeletor activates the super-computer where the clones work to disable the planetary shield.

Primus' sun withdraws out of regeneration behind a shell. This causes an ice age to break out as He-Man works to preserve all life on Primus.

After Caz injures his leg pretending to be a Galactic Guardian, the Scientists of Primus give him a high-tech Medi-Suit powered by energy crystals that can help him move around until his leg is fully healed. This Medi-Suit gives Caz some abilities. Knowing that the Scientis of Primus put too many energy crystals in it, Master Sebrian advises He-Man to stop Caz before he gets hurt. Unfortunately Skeletor lures Caz to a trap on the planet Dectis causing He-Man, Sagitar, and Tuskador to go rescue him.

He-Man and Skeletor arrive on the planet Machina where its inhabitants are controlled by machines. While He-Man joins a resistance and fights for the independence of Machina's inhabitants, Skeletor has other plans.

Following a recent fight, the Galactic Guardians reminisce about past battles. In a flashback, it is shown that a transporter ship carrying poison gas was blown off course as Hydron and Flipshot train the Galactic Guardians' new recruits Artilla, Spinwit, Tuskador, and the previously-unknown Sagitar. Skeletor plans to destroy the ship with the Galactic Guardians still on board.

An asteroid gets passed Primus' planetary shield. As the lasers from the Starship Eternia doesn't phase it, He-Man heads out to intercept it and deflects it into the sea. Master Sebrian discovers that the asteroid is causing trouble for the underwater city of Serus where Hydron is from. Learning form Hydron's sister Aquata about Serus' flooding, the Galactic Guardians work to seal the crack. Soon, they must deal with the living asteroid Keto who plans to drain Primus of its energy.

The Scientists of Primus inform Master Sebrian that a deadly gas called the Black Omega has the power to destroy Primus' planetary shield and is located on Omega 4, a frozen planet at the edge of the Tri-Solar Galaxy. Master Sebrian agrees with the Scientists' suggestions to have He-Man destroy the planet with the Black Omega. When He-Man, Spinwit, and Tuskador on Omega 4, he discovers that there are some inhabitants on Omega 4 enslaved by the Mutant Maxus and his two-headed servant named Zark who were exiled there by Skeletor. Maxus and Zark are using the slaves to harvest the Black Omega in order to get on Skeletor's good side.

Master Sebrian and Mara crash land in a remote area of Denebria. When He-Man arrives on Denebria to save them, he encounters some friendly Mutants who claim that they were once humans.

He-Man is homesick for Eternia as the Sorceress of Castle Grayskull to send Teela to visit him. Meanwhile, Skeletor obtains a volume of a spellbook called the Encyclopedia of Evil and plans to obtain the entire collection with the help of Flogg, B.H., and Quakke while also taking Grot as a hostage.

Skeletor gets his hands on some anxiety gas which causes any males exposed to it to become trembling cowards and has an opposite on females. Now it is up to the females to defend Primus from the Evil Mutants.

The city of Levitan is in need of more berillium to run its generators. Master Sebrian's old friend Treybius travels to Primus to deliver the berillium where his ship the Star Trader is intercepted by the Evil Mutants. After being rescued by the Galactic Guardians, Treybius accompanies He-Man, Master Sebrian, and the Galactic Guardians to Denebria to reclaim the Star Trader and get the berillium before Levitan crashes to the ground.

The Galactic Guardians and the Evil Mutants remember their recent battle in the Quagmi Swamps. Each side recaps what happened during the battle.

In order to bring law and order to Gorn City, Flogg takes Skeletor's suggestion to appoint Flipshot as its new sheriff so that Skeletor can spring a trap for He-Man. Flipshot and Spinwit gain the support of Gorn City's mayor Seeka who has no vendetta against Primus. As Skeletor and the ex-mayor Korac orchestrate events to lure Tyroc and the Ugly Bunch to face He-Man by allowing Byloc to be captured, He-Man gains the assistance of Meliac to help defeat them.

A large meeting of magic users is occurring on Primus. The Opague magician Ramlin is in attendance as he has a plan to steal everyone's magic.

During an event on Primus where different inventions are being shown off, Skeletor has Grr steal a cloning device. When He-Man works to reclaim the device, the Evil Mutants obtain his DNA sample which Skeletor uses to create a clone he calls "He-Slave" which he plans to use to defeat He-Man.

He-Man gets a big fan in the form of an old lady named Melindra. When the Galactic Guardians go on a mission, they are unaware that Melindra has stowed away on the Starship Eternia.

Skeletor uses an invention to get into the Dream Zone. When he attacks the internal device that maintains the concentrated subconscious that helps to protect Primus, He-Man must enter the Dream Zone to confront Skeletor.

Skeletor uses an intelligence amplifier given to him by Korac to enhance the intelligence of the Evil Mutants. Even when they succeed in overcoming He-Man, the Evil Mutants start being intellectually superior to Skeletor.

Adam is on trial for running away during an attack by the Evil Mutants and a supposed act of treachery when he was secretly transforming into He-Man with Werban prosecuting him. Despite Master Sebrian attempting to speak on Adam's behalf, Adam is found guilty by Werban and is to be shipped off to the Prison Moon for the next 18 Telks. Meanwhile, Skeletor and Flogg enlist their inside person to plant a disruption bomb at the Titus Observatory to serve as a diversion for the Evil Mutants' next attack.

While on a reconnaissance mission to Primus' moon, He-Man and the Scientists of Primus discover a plant species that is harmful to the Mutants of Denebria. He-Man harvests the plants and brings them to Primus in hopes that it can keep away the Evil Mutants.

Flogg has obtained some new laser cannons with their range being a threat to Primus. Now He-Man and the Galactic Guardians must infiltrate Nordor and destroy the cannons before it can be used on Primus.

A bug on the Starship Eternia causes it to land on Denebria. Sagitar rescues a Mutant named Felca who is the future bride of Slush Head. Discovering that Sagitar rescued Felca, Slush Head agrees to help the Galactic Guardians get a new part for the Starship Eternia. Flogg finds out that Slush Head invited the Galactic Guardians to his wedding as Skeletor sees this as an opportunity to get rid of them once and for all.

An unbeatable gladiator champion named Dreadator is persuaded by Skeletor to fight He-Man. To prove that he is the best warrior in the universe, Dreadtor challenges He-Man to a duel.

The Mutant Mothership is caught in a space storm. Displeased with Flogg's decisions, Staghorn persuades B.H. and Quakke into starting a mutiny.

Slush Head and Staghorn discover a 1980s rock star on a desolate planet. When they take the rock star to Denebria to meet their fellow Mutants, Skeletor plans to use the rock star in his plot to destroy He-Man.

After helping to accompany Hydron, Flipshot and Gepple to study the solar flares, He-Man learns that Sagitar's strange behavior comes from the Running of the Herd vision as He-Man allows the group to head to Equinos to celebrate the Horse Lords' heritage or else perish. Flogg plans to be present at the Running of the Herd with Skeletor, Slush Head, Staghorn, and the Mutant Troopers as a way to target Sagitar while threatening the planet's destruction to General Nekor.

He-Man, Hydron, Flipshot, Sagitar, and Mara head to the planet Nekron to negotiate peace between the Mytes led by President Pell and the Gleanons led by General Nifel. They come to the aid of the Mytes when Crita collaborates with General Nifel in capturing President Pell in order to access the Transium Mines and obtain enough to make weapons for the Evil Mutants.

Mara contacts Master Sebrian to inform him of a radio signal from the planet Zil that has been uninhabitable due to the storms there. He-Man and Spinwit head to Zil where they meet their inhabitants who would like Spinwit to save them due to the crystals for their Tornado Machines are almost out of power. Meanwhile, Skeletor takes B.H. and Quakke with him to attack Zil.

President Pell sends his ambassador Bimo to Primus to showcase his robot Kog. Upon being contacted by General Nifel and Crita, Skeletor and Flogg plan to reprogram Kog to destroy Levitan where they have the Gleanons' programmer Private Dobson do the job. Upon Bimo and Kog's arrival, Optikk activates Kog to attack as he, Staghorn, Hoove, Slush Head, B.H., and Quakke begin their attack on Levitan.

The Mytes and the Gleanons are still at each other. General Nifel and Crita have a plan to subjugate the Mytes. Now He-Man and Mara must help the Mytes and thwart the Gleanons' plot.

To cut off the supplies to Primus, Skeletor and Flogg hatch a plan to conquer the planets in the Tri-Solar Galaxy. The planet Danzig is their first stop as He-Man, Flipshot, and Ambassador Bimo come to Danzig's defense.

Skeletor causes a meteor to head to Primus while Crita starts a large offensive against the Mytes. With He-Man busy dealing with the meteor, Mara is on her own defending the Mytes from Crita and General Nifel.

Skeletor and Korac free some mercenaries and promises them a reward if they terrorize Primus. When He-Man tries to infiltrate them and gets caught, Ambassador Bimo becomes his unlikely rescuer.

The Galactic Guardians and the Evil Mutants get involved with a battle between two gigantic stars. When the battle is finished, both parties must fight each other.

He-Man and the Galactic Guardians head to the planet Crelus to find the blacksmith Yolt to make weapons for the upcoming Games. Though Skeletor and Flogg have a plan to make Crelus make weapons for them and fool him into thinking that the Galactic Guardians are the bad guys.

The Galactic Guardians are in need of a trainer for the upcoming mutant invasion. When they arrive on the planet Nekron, they encounter the shady and unusually large Myte named Wulk who trains them until it comes to a certain maze where he has plans of his own that involves working Skeletor to take revenge on the Mytes.

The Galactic Guardians and the Evil Mutants compete against each other in the Games. While the Evil Mutants win the first round thanks to some trickery, the Galactic Guardians work to turn the tide against them.

He-Man and the Galactic Guardians celebrate their victory in the Games. After failing to blow up the Great Hall with a stolen astrosub that has a Transium Ore, Skeletor and Flogg take hostages with the condition of their release is that He-Man must face Skeletor in the Arena.

In light of the Galactic Guardians' latest victory, Flogg leads the Evil Mutants and the entire Denebrian forces in their final battle against Primus.