It is important to mention that all Protoss were designed for war and fighting by the Xel'Naga. That is why they can all create a Psi-Shield and a Psi-Sword. The division into separate castes is part of the Khala and was not designed by the Xel'Naga.
The Protoss appear to be physically weak, but their simple appearance, without large muscles or any obvious powers, hides their true strength. Although the Protoss stand taller than an average human male, their limbs are thinner with stronger and smaller muscles. Their faces are devoid of most common humanoid features. They have two eyes below a pronounced brow and a long chin, but they have no nose, no mouth, and no ears. Some Protoss have quite different looking faces, with dry and cracked skin and sharply pointed chins while others have very smooth faces and round chins, but none have a visible nose or mouth. Protoss skin color also varies dramatically from individual to individual. Each clan has a distinctive skin color ranging from blue to purple. On the back of their heads grows what looks much like hair but is much thicker and grows in a pattern resembling dreadlocks. It is believed that the Protoss feed on P.P.E. energy because of a lack of any other method of ingestion, but this is not entirely true. The Protoss can feed on P.P.E. and for many centuries that is all that sustained them on Aiur, but as they began exploring other planets and building new colonies, the Protoss needed to find a way to continue feeding on planets that were not rich in magical energy.
When the Protoss feed on P.P.E. from ley lines or from other creatures, their bodies convert the magic energy into the normal energy (measured in calories) that their bodies use to survive. P.P.E. energy is much more efficient then any other means of nourishment because the magical energy is directly converted into any kind of vitamins or minerals that the bodies needs. With their advanced technology the Protoss have developed a means of converting normal food into highly concentrated nutrition patches that can be attached on any area of exposed skin. The patches contain all necessary nourishment, vitamins, and minerals for a Protoss to survive several days. The development of the patches allowed the Protoss to explore and even colonize planets that were not rich in magical energy. Even with magical energy or the nutrition patches, the Protoss still need water to survive. A Protoss drinks water through the palms of its hands. When preparing to drink, the skin on the palms changes into a sponge-like texture and quickly absorbs any liquid. The Protoss can digest any water-based liquid to get water and their bodies naturally separate the water from any other material in the liquid, their bodies will use every bit of other material from the liquid, producing no waste.
Protoss require only about 4 hours of sleep every 24-hour day, but can go up to three days without any sleep before they begin to suffer penalties. Even without visible ears or a nose the Protoss still possess the senses of smell and hearing at a level equal to humans. Since they have no mouth, the Protoss do not have a sense of taste or taste buds and they cannot be poisoned by ingested food, although poison in a nutrient patch will still affect them.
The Protoss were genetically engineered to possess many psionic powers. In the same way that most animals naturally possess certain psychic powers, all Protoss possess several powerful abilities. The Xel’Naga had created them to be able to survive under most conditions; they can sustain themselves much easier then most races, feeding on either magical energy or regular food in order to produce the calories they need. The Protoss must absorb 100 PPE every week if they are to remain perfectly healthy. Every week that they do not feed is the equivalent to a human being starved for the same amount of time. The Protoss can also combine regular nutrition with magic energy. The two amounts need to balance each other out, so if a Protoss Warrior consumed 50 PPE during a single week, he must also have ingested half of the required weekly nutrition from the patches or he will begin to go hungry. Protoss require half as much daily calories as a human does, as their bodies are much better at processing and using stored energy.
The nerve appendages on the back of the head of a Protoss serve several functions. They are very sensitive to air movements, and if a Protoss is standing still, it can detect motion within a radius of 200' (61 m). The appendages also give the Protoss a telepathic link with each other. If the appendages are cut off or removed, a Protoss would lose their psychic ability of Telepathy. The appendages will begin to grow back after 1D4 months; once they begin to grow they increase in length at a rate of 1" (3 cm) every week until they are full length. Fully grown, the appendages measure 3' (1 m) in length. They have to be at least 2' in order for the Protoss to use their natural telepathy. Also, the Protoss can communicate through vocal sound and often combine both telepathy and sounds to communicate with each other. They produce sound by taking in air through special slits in their necks resembling gills. These slits also provide the Protoss with the air they breathe and can work underwater. A special filtering system allows the Protoss to filter out most airborne toxins and gases, but it is not completely effective. Their ability to breathe underwater is a genetically engineered ability given to them by the Xel’Naga, the Protoss did not directly evolve from a water creature and do not live naturally in water.
The Protoss were designed as a warrior race and as such their methods of reproduction and raising children are different then most races. Like Humans, Protoss can mate year round, and after a six month pregnancy, a Protoss woman will deliver a litter of 1D4+1 Protoss babies. With such a large number of children per pregnancy, most Protoss consider all of the children in their community to belong to the community and resources are shared to look after the children. Even with this sharing of resources to look after and raise the children, the child's original parents are still their parents, and being a parent is a source of pride among most Protoss. Protoss children develop quickly considering their long life span and after only thirty years, they have reached full maturity and can produce children of their own until they become infertile at the age of 800+1D20x10. Infertile males and females are treated as elders by younger Protoss and each may have hundreds of children spread throughout the planets and colonies controlled by the Protoss.
With such a long life and a high birth rate, many outsiders wonder why there are not more Protoss and the answer is relatively simple, the Protoss suffer from a high rate of child mortality. For whatever reason, when the Xel'Naga created the Protoss they created them with incredible psionic powers, and some children have a higher level of these powers then others, the Zealots and High Templar are examples of this, but others have so much psionic power that they become a danger to others if their abilities are not properly controlled. Most times these children eventually gain control over their powers and rejoin society, but there are too many of them that never learn to control their powers and as they approach puberty, their powers continue grow and they begin to grow unstable. Eventually, the children that are unable to control their raging energies are consumed by their own power. What would startle most people is that this happens to nearly 1 out of every 5 Protoss children. The pain of losing their children prevents most Protoss couples from creating new litters as often as they could, that and it would be very expensive raising that many children, so the average Protoss couple generally mate for life and produce only three to five litters throughout their entire life.
