The BETA are usually commanded by the Superior, a BETA strain best described as a 'biological quantum computer'.

This chart, which showcases force composition in a large-scale BETA attack force, is based on information from the special episode of Total Eclipse. During an offensive push by the BETA, expect to see several hundred to tens of thousands of Tank-, Grappler- and Destroyer-class, as well several Fort-class and dozens if not hundreds of Laser/Heavy-Laser-class BETA in the mix as well. The best defence is to have pilots being able to respond quickly and efficiently to a sudden incursion, and to quickly deal with an incoming force if it is detected early enough. In addition, there is no real way to detect a BETA offensive from far off ground-based sonic sensors and recon satellites are at the mercy of the weather and mechanical failure. The Laser-class is the BETA's greatest card to play. However this later changed to give higher priority to manned systems thus making TSFs which have powerful computers as well as having a human pilot a higher priority for the Laser class BETA. The laser classes also prioritize targets based the computer systems they have thus making missiles and drones higher priority targets than artillery shells and more advanced they were higher the priority. Their lasers can instantly destroy both air and ground enemy units from beyond visual ranges, and due to the fact that a typical low-threat BETA encounter would usually number several dozen Grappler-, Tank-, and Destroyer-class means that without air support, human armies would typically find themselves outmatched and outnumbered in a ground war. What allows them to not just stand toe-to-toe with humanity's forces, but to actually dominate them, however, are the Laser-class and Heavy Laser-class BETA.

They have been likened to the space monsters from ' Gunbuster' (and to a lesser extent, the Buff Clan in ' Space Runaway Ideon'): their strength lies in their numbers and capability for a battle of attrition, and they are notable for being incredibly ugly in appearance, sometimes scaring even battle-hardened soldiers.ДЇ-4s facing a wave of Destroyer-class BETA.ДЄs an alien force created for mining, the BETA center their strategies around total dominance with overwhelming numbers the areas that they take are eventually mined of all possible resources, leaving a barren wasteland behind that is unfit for supporting human life for decades to come. During Chronicles 03: Rebirth though, the reason is revealed to be that because many of the BETA forms bear a resemblance to humans or have humanoid features, the general populace may fear them to be an out-of-control biological weapon developed by a rogue nation rather than alien invaders. All that mankind knows of them during Unlimited and at the start of Alternative is that they are (obviously) hostile, are carbon-based lifeforms (this was discovered when specimens were examined in Alternative 2), and do not consider humans to be living beings (this was found out through the readings of Soviet espers in Alternative 3).Дuring MLU/A it is revealed that only soldiers and eishi that have been officially commissioned are allowed to see the true forms of the BETA, which are classified at the highest level to anyone else. Their very existence is shrouded in mystery. They cannot fly, and the Laser and Heavy Laser-class BETAВ shoot down anything that does, rendering aircraft useless and making any aerial military operations much more difficult.

The BETA vary greatly in size, with the smallest identified strain (Soldier-class) being around 3 meters tall, and the largest identified strains (Fort-class) at over 60 meters tall. By 2001, the world population was down to about 1 billion people. They quickly spread from their landing point, Kashgar, and proceeded to invade the Eurasian, Middle Eastern and Asian regions when they finally reached Japan in 1998, 36 million people were killed within a week.

They arrived on the Moon in 1967 and, after a brief conflict with humanity's space forces, invaded Earth in 1973. Muv-Luv Unlimited and Alternative, as well as their associated side-stories, take place in alternate universes where the BETA were first spotted on Mars in 1958. BETA are featured in Muv-Luv Unlimited/ Alternative and their related spinoff works, where they are the primary antagonistic faction against humanity's forces.

Muv luv beta png