Emperor Darius and the Generals
The Principle Antagonists of the series, Emperor Darius and his Four Generals were five Giant Robots that serve as the Military Power Structure that commanded all forces on Zela and held a tyrannical reign over its civilian Population, who are in fact reveal to be Peaceful in nature themselves.

Created to serve as both as God and Ruler in the Zelans desperate time of need following the appearance of the Black Hole, Darius force what survived of the Civilization underground with the help of an artificial Sun as the once habitable biosphere on the surface was ravaged. Over time, the Electronic Computer would be given a Gigantic Robotic Body to move around, that while lanky and with thin limbs, it was strong in combat. Darius would later covered its robotic form with a red face whose mouth was located on the forehead, with Blue hair, green eye brows and mustache, and long green tendrils on the sides. He wore a black cape with a purple undergarment. Darius was capable of Sword fighting, as well had eye laser beams and super strength to boot, though its weak point in the end was the Electronic Brain, visibly located in the forehead.

While the Zelans found some reprieve from the disaster, the Planet days were numbered as it began to be in pulled by the Black Hole. Therefor, Darius began the work to build a powerful Army to invade Earth, once an ancient Colony of the Zelans, and the first Planet they trotted on in their first space travel centuries ago; itself stored with left overs, weapons, facilities, and allies of their reign. To assist, he would send (or awaken ancient) Mechanical Monsters called Dark Horror Monsters, which serve as the principle weapons of the Army.

Darius would also converted portions of the population into two variants of Soldiers: the Dark Knights, often seeing as Pilots of the Mechanical Monsters or mission/base commanders, and the Dark Avian Corp, which were the principle foot soldiers of the army – with their morals and compassion been excise from them in a brain washing process, as the Hierarchy saw Emotions as weak, and often frown upon it, using these for means to an end, but disdain it all together.

To command The Dark Horror Army, he created his Four Generals:

Desmon: Perhaps, one would describe him as the leader of the Four Generals, though this is debatable, as all four of them would share equal Power; often the most forgettable, really, until he shows up on screen (like, you had no idea how often I confused him with Dankell), so much so, he didn't had a define personality or did anything remarkable that would set him apart; he was just there. He was pink and purple in color, with his face covered with a mask, attached to the rest of his black and Red cloak, with horns on top of his head, and had his ears visible. He was the 2nd General killed in the final battle, when crushed by the Daiku Maryu's treads.

Dankell: The Blue General. He was the Scientist of the quartet, and would on rare occasion showed "some" level of humanity, wanting to begin the evacuation of the Civilian Population at the earliest when Zelans days were numbered, but was as equally as cold as his creator and colleagues, in one occasion testing a weapon on two Avian Corp Soldiers in front of the Emperor. He was the last General Standing, spouting in defiance before he was rapidly cut down by Gaiking's Double (Counter) Cross.

Asmoff: Identifiable by it's green colors and bug eye helmet, he holds the distinct pleasure to be the first General to come in direct Contact in person with the Daiku Maryu crew after they were captured in Egypt. Interestingly, he was the only General whose head cover was separate from the cape, nor did it sport horns or the sharp teeth seeing in the other Generals; compare to his compatriots, he was a bit lanky, though this may be animation errors at times. He was in the same line as Killer, for the use of force, but would also caution restrain. Asmoff was the first General to be killed when Gaiking came to the assistance of the Daiku Maryu during the final Battle, been shot in the back with Saur Geyser, getting a face reveal briefly for a few seconds when his helmet is blown off.

Killer: The more brutish and robust of the four Generals, often going for force to solve the situation that developed in the field and he would not shy of killing Cowards that ran away; ironically, prior to the final battle, he had become something of a coward himself, after seeing how Gaiking and the Daiku Maryu had beaten everything they throw at them. His terror of his impeding demise is evident when Gaiking fired its Hydro Blazer at him, a terrified scream are his last words before been blown away.

The Generals would travel space on their Grotestar Vessels (or Grotestors), which resemble sharks, and together they would use an attack technique called the Death Cross – this would help them travel the distances between Earth and Zela, or create a Black Hole like phenomenon (the Reverse Death Cross). In combat they share the same abilities, been swordsmen and fired EM laser beams from their eyes, however, this was only seeing in the final battle.

The Generals, though been giant Mechanical beings, were themselves smaller to Darius, about Half his size (and at time shown to be a third his size, though this may be rushed or animation errors), and generally, supervise and directed the missions and Attack plans from their ships, not taking any form of direct combat themselves until in the Final Battle with Team Daiku Maryu, when the whole army and the Monsters had been decimated by this point, contempt to be on their ships and using the Death Cross Phenomenon.

Funny enough, despite been robots, they could get Drunk; this detail could indicate the Generals may had been normal Zelans converted into these Mechanical Constructs, which they had done so with other creatures in the series (Big Mowrls and Nessie Q), though this is conjuncture at best and is never really explain. Darius would rarely intervene in the military operations, doing so when arguments develop between the Four Generals, issuing orders directly or when in Council with them.

Perhaps more interestingly, Darius and his Generals weren't the only known instances of Giant Zelan Rulers in the history of the race; in Episode 30, "The Dinosaur of the Jungle" the Daiku Maryu Team discovers Pictorials of the Maya Civilization having been enslaved in the past by giant overlords, forcing them to build Rockets, the rulers turned out to be Ancient Zelans. Whether this is actual depiction of the Ancient Zelan overlords or an interpretation of their status it is NOT explain.

Ideologically wise, the hierarchy was perpetually stuck in a "might makes right" mindset, mostly because the Emperor and the Generals, as machines, understood force as means to an end, thus all ideas of peaceful co-existence with the Earthlings was out of the question to them; they must conquer Earth, because it was their first Colony in the distant past and must enslave or, if necessary, eradicate Humankind. Is this mindset that often leads many Zelans, who either volunteer or are force into the Army via brainwash, to pay the price for the arrogance of these Giant Robots, seeing the population as nothing as tools and canon fodder for their War Machine are constantly slaughter. In the end, thanks to this hard-line stands, with all their plans having failed and Zela on verge of destruction, what's left of the population had become too tired of war, demanding Peace Negotiations be made with the Earthlings to allow them to settle on Earth in peaceful coexistence.

An irate Emperor and the Generals leave with what's left of the entire army from Zela, its people staying behind to meet their end; but (EGAD, BRAIN!) unbeknownst to him, an elderly Scientist had secretly developed a Gravity Field Generator; this protects the last city and its remaining inhabitants from the Black Hole and escape the demise of their home world while the Emperor and the Army head for Earth with the same unconditional path for violence that has misguided them since their creation, and despite all the traps they set, they are slaughter by the heroes of the Daiku Maryu, with the Emperor himself, reveal in its true Robotic Construct form, falling last when Gaiking scores a direct hit on his Electronic Brain.

As the heroes celebrate their victory by wishing for a better future to a passing Shooting Star, the Zela survivors of the Shield Protected City gracefully pass by the Earth under a vow to forge for themselves a path forward for a better future in search for new home, leaving for good the dark Path Darius tried to dragged them into in the past.