The Kodan Empire is an evil empire featured in the movie, The Last Starfighter.
The Kodan Empire seems to feature at least two main species: one that acts as the commanders and leaders of the organization (most likely the namesake Kodan), and one that makes up a majority of their crews. The Kodan make heavy use of cyborg technology in order to control the secondary species that serves as their crews. Control is exercised to the point that the crewmen act more or less like robots, in the manner similar to the crew in the movie, The Black Hole. If their cyborg helmets are removed, Kodan crew are immediately incapacitated, and if their circuitry is damaged, they die very quickly. Kodan crews and fighter pilots are controlled to the point that they can not act effectively if a control signal interface on the main Command Ship is damaged or destroyed. Even some of their officers can't disobey a designated fleet commander until that commander's decisions put their fleet in perceived grave danger.
Only two types of Kodan vessels have been seen: a large capital ship called a "command ship" and a simple "deck fighter". The command ship is large and heavily armed, but it does not have enough weapons to effectively counter a determined enemy attack. It relies mainly on its onboard armada of deck fighters for defensive and offensive capability. This makes its roll similar to that of a heavy strike carrier rather then a battleship.
The deck fighters, due to the Kodan's fears of rebellion, are only lightly armed. Their crews are connected in an interdependent network that limits their effectiveness unless supported by a command ship and its communication turret. The fighters are armed with at least four energy weapon turrets on their wings and a pair of missile tubes. They are not heavily armored and can be quickly destroyed by Star League weapons.
The Kodan make use of assassination agents called Zando-Zan. It is not clear whether these beings are genetically engineered or the Kodan use their mind control technology to program them to be unrelenting killers. Once a Zando-Zan has been given a target, it will pursue that target until one or the other is dead. A Zando-Zan has the ability to assimilate the appearance of any being it comes into contact with in order to disguise itself. This process results in the death of the being that is copied. Zando-Zans are known for their horrible smell, their only disadvantage as it could allow a target to evade an attack from one of them no matter what form they appear in, though when disguised, this scent appears to be partially suppressed. They also can control their limbs even when those limbs are separated from their bodies.
Xur is a Rylon --son of the Star League's president-- who defected to the Kodan, taking with him the secret to penetrating the Frontier, the Star League's defensive barrier. His knowledge allowed a Kodan Armada under his command to breach a hole in the Frontier and attack the Star League. He also used his knowledge of the military installations of the Star League to plan a preemptive attack on the Star League's starfighter base on Rylos. The movie makes it fairly obvious that Xur did not share his information with the Kodan, he just outfitted his assigned Armada with the required equipment. He was also the leader of a cult with the goal of making him Emperor of Rylos and -- by extension -- the rest of the Star League. Xur also used his Xurian Cult to recruit spies deep within Starfighter Command. The position held by his known spy was perfect, the accountant in charge of paying out bounties for new starfighter recruits. It was one of his deep operatives that disabled the starfighter base's automated defense cannons, making the destruction of the base possible.
The Xurian Cult makes use of modified cargo ships as attack vessels. The vessels are armed with two centerline energy weapons and what must be improvised missile racks. These vessels, like the Kodan deck fighters, are not heavily armed and -- because they are based on cargo vessels -- not too effective in combat.
When we see members of Xur's cult who are not serving as spies, we can see that Xur has begun to install the Kodan's electronic mind control technology into them. This behavior shows that Xur does not believe in a fully autonomous society and would rather use technology to ensure loyalty. The fact that he does not share his secrets with the Kodan at large proves that even he does not trust the Kodan.
Kodan ships, due to their paranoia, are not as powerful as the level of their technology suggests that they could possibly be. The Kodan themselves consider the Gunstars of the Star League to be so superior to their own ships that a single Gunstar attacking from the rear quarter of their fleet is considered a grave threat. Only the Borg seem to have developed more advanced cyborg technology.
It is uncertain how they would perform against other science fiction empires in battle.