The cerulean, indigo, purple, and violet castes are considered to be the "highblood" castes, though it should be said that the status of the cerulean caste is often informally debated. Midbloods in particular tend to be of the opinion that ceruleans are of their lot, whereas ceruleans often detest the notion. On average, midbloods range from 5'8"-6'4" (173-193cm) at ten sweeps of age (hornless height), and can be expected to grow up to fifty percent taller as they approach seniority.

Highbloods are generally significantly more powerful in physical form than lower castes, gaining muscle with greater ease and efficiency. The muscular structure of highbloods is such that, compared to equal weight in muscle to those of a lower caste, they can be expected to be roughly two times as strong. Ceruleans inherit this benefit only partially, being approximately fifty percent more powerful on average. In general, highbloods have higher caloric demands as a result of their enhanced metabolism.

Ceruleans will quite often have optical mutations such as multiple eyes, split or shaped pupils, or both. Ceruleans born with one eye are rare, and slated to be culled in the spawning process. Regardless of their eyes, ceruleans can also have psychic conditions, particularly those which allow them to interface with the neurological processes of others; possible symptoms include memory inception and alteration, telepathy, control of some or all of the body through the nervous system, as well as thought and/or dream reading. Their symptoms will never include the ability to produce hallucinatory sensations, and in general, the share of ceruleans who do possess psychic conditions is considerably less than other psychically-enabled castes.

Purplebloods may possess psychic conditions colloquially referred to as "chucklevoodoos", this being despite the fact that the Clown Church of the ancient era is dead, buried, outlawed, and incinerated, as is anything to do with clowns as a subject. Symptoms of "chucklevoodoos" almost always include the ability to alter the perception of another individual, causing them to experience hallucinations; psychic purplebloods can usually range over one or two senses only. "Chucklevoodoos" do not directly manipulate emotion itself, as is commonly misconceived, but a skilled wielder may be able to predictably produce sensations that evoke the desired response in their target.

Highbloods are often assigned to the departments of Ground Conflict, Aerospace Conflict, Medicine, Research & Development, and Legislaceration. Highbloods are more likely to occupy upper positions in whichever department they are assigned, particularly in the R&D and Conflict departments.