Power Rangers Season 21

When The Emperor nearly defeats the Rangers after a massive attack, the Rangers get help from Legendary Rangers from the past.

Emperor Mavro launches an attack on Earth by calling all Armada forces across the galaxy to drop what they are doing in their positions and head to Earth. He also sends Levira to fight the Rangers in order to redeem herself for the death of Prince Vekar and Vrak and to make up for Damaras' failure.

Emperor Mavro comes to Earth following the deaths of his sons Vrak and Prince Vekar and replaces Prince Vekar's fleet with his own fleet. He also plans to punish Damaras for what happened to Prince Vekar, yet gives a chance to Damaras to redeem himself by destroying the Power Rangers.

With two of the drills in the Earth, the Rangers must rescue Orion from Vrak and free Robo Knight from Vrak's control before the final drill can be placed.

Following Prince Vekar's destruction, Vrak resurfaces and makes his latest plan to destroy Earth with the help of a reprogrammed Robo Knight.

The Rangers finally battle Prince Vekar face to face when he comes to Earth armed with his very own Megazord.

The Rangers are lured away from Earth and into Corinth by Professor Cog who locks the wormhole to Corinth. While the Rangers work to tame the Turbo Falcon Zord, Professor Cog and his Grinders attack Earth and runs into competition in the form of the Armada. The Rangers must find a way to tame the Turbo Falcon Zord and find a way back to Earth to stop Professor Cog.

A body-swapping monster named Tranceferer switches Jake and Noah's bodies while on a mission to swap the bodies of high-ranking people. While Tranceferer continues his mission, the monster Turtlelini is sent down to distract the Rangers causing Jake and Noah to handle fighting in each other's bodies.

When the Legendary Megazord is damaged in a fight against Desolar (who is stealing the happiness from humans in order to cure Prince Vekar's cold), Emma uses unconventional methods to defeat this unusual monster.

A love potion made by Invidious accidentally makes Levira fall in love with Jake. Upon discovering this, Invidious plans to eliminate Jake so that he can have Levira for himself.

The Rangers are sidetracked from fighting Sirjinkor when Tensou develops amnesia and wanders away from the Command Center.

When the Rangers are sidelined by an energy-draining monster named Skeltox, Jake must get over his jealousy of Orion and help him master the powers of the Sixth Rangers in order to defeat Skeltox.

Orion explains his origins to the Rangers, Gosei, and Tensou. Meanwhile, Damaras sends Commander Osegain to Earth in a plot to destroy Orion.

When the Armada sends down X Borg platoons after X Borg platoons, the Megaforce Rangers have their encounter with the Silver Ranger even when they are facing off against Gorgax.

After the magnetic monster Pacha Chamak steals the Power Rangers' weapons, Jake and Emma consult with Casey Rhodes (the Jungle Fury Red Ranger who is now a part-time zookeeper) to learn a special form of martial arts.

The emperor unleashes a powerful monster called Matacore to combat the Rangers. When fighting Matacore, the Power Rangers meet Jayden (the Red Samurai Ranger) and Mentor Ji who provide a disk to help them fight Matacore.

The Power Rangers take the Sky Ship to Animaria to look for the Red Lion Wild Zord. They soon find themselves in competition against General Peluso who is also after the Red Lion Wild Zord.

After being defeated in battle by a master swordsman monster called Skatana, Noah wonders if he is worthy to be a Power Ranger anymore and ends up training to counter Skatana's attacks.

While the rest of the team works with the civilians to rebuild their city, Troy stumbles upon a plot by the Armada to launch missiles at major cities throughout the world.

With that battle won, the civilians attempt to restore order. Back in the classroom, Mr. Burley lectures with new purpose, stating that when faced with great adversity the human spirit will always prevail. On the beach where Robo Knight fell, Troy remains pensive, more determined than ever to find their lost friend.