"Aren't you guys legendarily racist?"The Kaylon are a species of synthetic, mechanical lifeforms from the planet Kaylon 1, affiliated with the Planetary Union. By virtue of their mechanical physiology, they regard themselves as superior to biological species.
"My planet regards humans and other biological life-forms as inferior, if that is your inference." ― Ed Mercer and Isaac[source]
The Kaylon race evolved to have a technological level that is significantly higher than that of the majority of Planetary Union races. The only revealed species whose technology is comparable to that of the Kaylon are the Calivon. As such, they are one of the few species that the Calivon treat and converse with as equals. One example of superior Kaylon technology are the portable holographic emitters provided by Isaac to Ed Mercer and Gordon Malloy in order to infiltrate the Yakar.
The Planetary Union made contact with the Kaylon who declined to join the organization but nonetheless sent Isaac as a representative to observe and learn about the relationships and cultures of organic species.
Kaylons are not biological lifeforms, but are mechano-computational lifeforms. All Kaylon are assembled within a central production facility on their home planet of Kaylon 1. Any Kaylon that is viewed to not become a productive member of society is terminated as a program. Kaylons are also significantly smarter than Union species, with Isaac being able to interface with and access the programming of a 29th century device.
The only Kaylon seen thus far is Issac, who serves aboard the USS Orville as part of a cultural study program by the Kaylon as part of a diplomatic mission by the Union. Issac has a humanoid body layout, but it is not known if this is standard for his species or if his body was customized to ease interactions with the largely-humanoid Union; for example, while Issac does possess visible eyes, they are merely for aesthetic purposes, as Kaylons rely on internal sensors to view their surroundings, allowing Malloy to once decorate Issac's face with Mr Potato Head bits without Issac realising what had happened until the bridge crew pointed it out to him. In addition to this, they do not sleep, instead put in a "charging station" when they need to rest. Kaylons are also capable of mimicking the voice of any individual as well as transferring their consciousness into other mechanical receptacles.
A Kaylon's mechanical biology allows them to live for millions of years. As a result, they do not perceive time in the same manner as biological lifeforms with Isaac stating that spending 700 years on a planet would be more akin to 700 seconds from his perspective. Upon reuniting with the Orville, Isaac's physical body showed no signs of physical degradation. Kaylons also possess incredible strength, comparable to that of Xelayans. Though incredibly durable, they can be vaporized by the PM-488 Titan's maximum setting.