Mecha Anime

The fifth season of the Dokan-kun franchise. It aired within the "Dejisuta Teens" variety program.

In the middle of an all-out invasion by extra-dimensional aliens, rebel alien scientist Zeku gathers teenagers with various psychic powers, like Isamu. Once on board Zeku’s ship… and on board with his mission to defend the human race from extinction… Isamu and his fellow teens use mental energy to create enormous suits of armor with which to battle the Garadain Empire. Through the course of the series, the teammates fight each other, fall in love, and battle wherever necessary to protect Earth, whether that’s at home, in deep space, or even while trapped on the alien world itself.

(Source: Crunchyroll)

A boy finds a toy robot which turns out to not to be an ordinary toy.

After being accused of stealing military secrets, Dr. Demian escapes from custody and expose corruption within the military; but he's pursued by a strike force that operates an experimental robot that he developed.

(Source: eigoMANGA)

In the year 2100 the Earth is once again in danger. The group of brave teenagers set out in their giant robot to save humanity.

A movie recap of the Space Runaway Ideon TV Series.

Humanity's pursuit of knowledge leads them to the planet Solo, where they find mysterious remains of a long dead alien civilization, including the 3 part super robot 'Ideon', and a powerful warship. Using these, the Earthlings sent to investigate the ruins defend themselves in their constant conflicts against powerful aliens called the Buff Clan, who are in pursuit of 'Id', the mysterious energy that powers the Ideon.

(Source: Anime News Network)

Nicholas, a hypocritical ruler of the Zinba Empire, wants to expand his territory. His plan is to turn the Earth into his own private colony. His detailed plan starts by cutting off all of Earth's defense forces by destroying the city of Orion. Meanwhile. a group of youngsters are spending their vacation on Mars. Not until they discover the destruction on Earth do they realize the danger they are in. They find Dr. Han and Fred in an underground Cave. Dr. Han believes that somewhere on Earth there is an immortal bird called, The Phoenix King. He is said to be the guardian of the Earth and only this mythical creature can defeat Nicholas. Therefore, the adventurer's set off for the Phoenix's alleged home and the Earth's only hope.

(Source: Digiview Productions)

When a young boy called Hiro finds what appears to be a broken lighter in an empty field, it changes his life forever. This lighter is actually the Gold Lightan, a robot that fell to Earth from the Robot Dimension. When called upon to defend the Earth from Ivalda the Great's evil robots, Gold Lightan transforms into a giant super robot, known as the Golden Warrior. Gold Lightan joins forces with Hiro's and his gang, the One Pack Rangers to protect the Earth from the evil schemes of Ivalda the Great and his armored forces.

In the planet Deloyer, a colony of the Earth federation, Colonel Von Stein stages a coup d'etat on behalf of the Federation chairman Donan Cashim.

The Earth had become a wasteland of deserts as the survivors work to rebuild communities. Daigo Otaki is a young orphan raised by his uncle. Becoming an adult, Daigo discovers that Victor City was in fact planned by his father who was a genius scientist. Daigo's sister Saori had been managing it. She plead Daigo to take on the inheritance that Daigo's father left him, a super robot system known as Gordian. Daigo would join the Mechacon mechanic combat 18th regiment unit, an organization of law enforcers that defend Victor City against attacks from the Madokuta organization.

(Source: Gordian Warrior, Wikipedia)

Mitora Ootsuchi, who belongs to the tourism department of Ootsuchi Town Hall, is doing a rehearsal with other staff to promote the town. While touring various spots, such as the Gensui River and Kozuchi Shrine, a demon beast suddenly attacks. Ootsuchi and her friends are now faced with saving the town.

(Source: YouTube)

Takeo Watta inherits a company upon his father's death. The company focuses on space travel, and the transformable robot Trider-G7 is their greatest creation. When an evil space organization lead by Lord Zakuron starts attacking Earth, Watta has to use Trider in a more combat-oriented way.

(Source: Anime News Network)

A scourge is sweeping across the galaxy—a scourge called the Blasters! These devious and handily-numbered alien invaders conquer, devour, and destroy every civilized world they see—and now, their sights are set on Earth! But worry not, good children, because Earth has a top-secret countermeasure developed by Dr. Hoshi and the International Science Police Headquarters.

Our secret weapon is the mighty, towering super robot, Astroganger! Crafted from mysterious alien living metal, the robot Ganger has just one weakness—he's kinda dumb! Enter the best person for the job, Dr. Hoshi's ten-year-old son Kantaro.

By joining their powers together, Ganger and Kantaro fuse the incredible power of a fightin', flyin' robot with the uncompromisingly savage, decisive intelligence of a middle schooler: Astroganger! With their powers combined, they'll save the world approximately twenty-six times!

(Source: Discotek Media)

Flying Dougram battles in space.

Giant robot Daikengo flies through space to re-establish galactic peace; on-board prince Ryger, who ran away from his planet Emperius to defeat the menace out of his reign borders, in order to save his people; Cleo, corrupted prime minister's daughter, help him along with two nice little robots, Anike and Otoke. They fight evil Lady Baracross, leading invasion forces, with her assistant Roboleon, wearing a Napoleon style hat. Daikengo is the first robot with scuttles on his mouth. When he opens them, his vampire style teeth are shown and he can spit fire.

(Source: Anime News Network)

The story is about 16 years old boy Takeshi who recently formed an American football team at the BlueSky orphanage. One day the game is interuppted by a light in the sky. Takeshi discovers he is the son of the king of the planet Apolon, spirited away to Earth by his father's retainer Rabi to avoid death at the hands of General Dazaan. He turns out to have special energy abilities which can control UFO saucers from under the ocean floor, which in turn can become robots that are synchronized to their movements.

(Source: Wikipedia)

Second season of UFO Senshi Dai Apolon.

The evil Green Queen of Utopia, a planet destroyed by nuclear explosions, escapes to re-create her world by invading the Earth.

On route to the Earth she attacks a space tour, kidnapping the passengers and killing the Ninja Master who tries to save the space tourists..

The dead Ninja Master is discovered by our hero, Johnny Destiny one of the special star force Space Rangers who vows vengeance on the evil killer of his sensei and instructor in the ancient traditions of the sword of light..

Johnny, his assistant Jane and their Robot Cappy are taken prisoner by the tyrannical Green Queen and learn of her plan to conquer Earth....

...Only Johnny Destiny Space Ninja of the Rangers can stop her..

(Source: AniList.co)