Description
Demigods are the end result of a god and a human having a child together. Because these children are part god, they have above average reflexes, an affinity for the Greek language, and may have some level of control or skill over the realm of their godly parent. Many of them also have ADHD and dyslexia.

While most demigods are created much like regular humans, children of Athena are born from their mother's thoughts merging with their father's. In this way, Athena remains a virgin goddess and it reflects how she herself was born, sprouting from the head of Zeus. It is unknown if other virgin goddesses or gods in general have a special way to have children like Athena or Hecate.

When a demigod reaches a certain age, normally early teens, their powers start to manifest. At this time, demigods will release a scent that monsters are able to detect. This scent will become stronger if the child learns they are a demigod. Also, if the demigod is a child of a powerful god, the scent can become even stronger. If the child never learns that they are a demigod or they are a child of a minor god, monsters may overlook them. It is around this time that they are escorted to Camp Half-Blood usually by satyrs, where they are placed in one of the cabins, each honoring a different god or goddess.

Claiming
Claiming occurs when a god acknowledges his/her demigod offspring, usually by sending a hologram of their symbol of power to appear over the particular child's head, but some claimings are unique, such as when Aphrodite claims her children. They start glowing with a pink aura. After that they instantly look great (beautiful). The children of Aphrodite refer to this as Aphrodite's Blessing, which goes on for a while and can sometimes even go back when Aphrodite wills it to, but may fade after a while.

Whenever gods have a child with a human, it was the gods choice to claim that child or not. This was a sign that the demigod child was a son or daughter of a certain god. At Camp Half-Blood, being claimed is considered a great honor and they use this knowledge to sort you into the cabin of your godly parent.

However other demigods were never claimed, even after arriving at camp. It is unknown why, but it is mentioned that even the gods lose track of all the children they have with mortals. It is all possibly that some demigods aren't claimed to keep them safe, as once a demigods learns who they are, they may begin to attract monsters that wouldn't have noticed them before. At Camp Half-Blood, any unclaimed demigod was also placed in Hermes' Cabin.

As shown in The Sea of Monsters, monsters like Tyson can also be claimed by their godly parent, even though they aren't considered demigods. Despite claiming generally being a holographic image or a makeover in the case of children of Aphrodite, a demigod can be claimed simply by having a god appear to them and claim them as their child. In The Lightning Thief movie, Percy was not claimed by Poseidon like he was in the book. Chiron already knows he is Poseidon's son, and tells him when he gets to camp. It's possible that most demigods in ancient times weren't claimed and probably didn't know they were demigods. Most demigods in Ancient Greece lived much longer lives. If Zeus doesn't claim one of his children, that demigod is probably safe from Hera's wrath.

Most demigods wait to be claimed. Children of Athena are claimed at birth, while others have to demonstrate some form of their parents' trait to be noticed, either through cunning, powers, skills like archery, or even beauty. Otherwise, they are placed in Hermes' cabin, as he is the patron to travelers, anyone is welcomed there, including children of minor gods who aren't important enough to have a cabin.

Few demigods have full-blooded siblings (with the exception of twins), as their godly parent will usually leave their mortal consorts not long after a child is born, or sometimes even before that. However, some examples of demigod siblings in the series include Nico and Bianca di Angelo, Connor and Travis Stoll, Jason and Thalia Grace (who have the same father, but in different aspects), and Castor and Pollux.

Greek demigods often go on quests given to them by the Oracle of Delphi.

Appearance
Demigods are completely indistinguishable from humans. They do not have a divine form, however they do inherit some traits from their god parent's divine form. For example, Percy inherited Poseidon's black hair, sea-green eyes and brooding look, while Annabeth Chase inherited Athena's grey eyes. Thalia and Jason Grace inherited Zeus' electric blue eyes, and Nico and Bianca di Angelo inherited Hades' black hair, dark eyes, and pale skin. The children of Aphrodite inherit her beauty and appeal. The children of Hermes inherit his elfish facial features and Luke inherited his blue eyes. Children of Ares inherit his sneer and tall, bulky appearance. Children of Hephaestus, such as Leo Valdez, Jake Mason, Harley, Nyssa, and Beckendorf inherit his skills with mechanics, resulting in them normally having large muscles and calloused hands (from working in the forges all day long).

It's unknown if a demigods eye and hair color depends on what form their parent took while consorting with their mortal parents. Some demigods with the same divine parent have a different color.

Traits
There are ways to hide or mask the scent, but if a demigod realizes who they truly are, their scent will reach its peak. The scent of children of the Big Three is much more potent than that of the children of lesser gods. Demigods' personalities tend to vary based on their divine parenthood; for example Percy is reckless and rebellious resembling Poseidon and the untamed seas, Annabeth inherits her mother's wits and intelligence and Clarisse is very violent and warlike, much like her father. There are currently four known children of the Big Three: Percy Jackson (son of Poseidon), Thalia Grace (daughter of Zeus), Bianca di Angelo (daughter of Hades) & Nico di Angelo (son of Hades). Most demigods also have ADHD and/or dyslexia (though it varies from demigod to demigod). Demigods are relatively stronger, more agile, and more durable than regular mortals, and have more resistance to diseases.

Demigods have a distinct scent due to a spell cast by Lamia, a monstrous daughter of Hecate, which allows monsters to find them. Many demigods indirectly change the course of history, and demigod conflicts usually mirror conflicts in the real world; such as how when the Roman and Greek camps fought each other during the events of the American Civil War. Some powerful demigods can directly change some of the courses of history and can manipulate the minds of mortals in some events, using the the Mist to change what mortals see.

Demigod Abilities
The inherited powers of a demigod from their godly parent or ancestor. Although most share at least one trait of ADHD or Dyslexia, their abilities are dependent on their divine parentage. In The Lost Hero, the gods are shown to be able to influence what powers their children possess. They can also see through the Mist, though they may still be fooled when the Mist is very tightly woven. This clear sight is not exclusive to just demigods, as some humans may have this ability as well.

• Zeus' children have command over the domain of heaven as their father is lord of the sky. Born to one of the Big Three, they are more powerful than other demigods. In addition to natural leadership ability, they are known to possess great bravery and strength. They may also have control over lightning and wind.
  
• Poseidon's children are stronger than most demigods as their father is one of the Big Three. Most of them have power over his domain with the capacity to generate earthquakes and hurricanes and control and create water. They can also communicate telepathically with equine and sea creatures since Poseidon created horses.  They also have limited control over ice and cold.
  
• The power of Hades' children is greater than most demigods due to their father's status as one of the Big Three. As demigods of the Underworld they have control over all that is subject to his kingdom beneath the earth. In particular, their earth abilities surpass those of Poseidon's children. Children of Hades are some of the only demigods able to control and raise the dead.  They can also control and manipulate bones as well as have limited control over cold.
  
• Demeter's children are altruistic and passive half-bloods. Demigods of agriculture, they are diligent workers and naturally have a green thumb. They can manipulate crops among other forms of Flora.
  
• The children of Ares are more aggressive and martial than most demigods. As offspring of the war god, they have incredible martial abilities with an extensive knowledge of combat, as well as, superior strength and overall physical prowess. Some are even given a blessing of invincibility by their father for their bold courage and righteous wrath in battle.
  
• Although she is a virgin goddess, Athena conceives offspring through a meeting of minds with her lovers. Demigods of war and wisdom, Athena's children excel in intellectual pursuits, and have exceptional skill in warfare, particularly strategy. Children of Athena are masters at invention and strategy and have a high knowledge and skill with weaponry. In The Mark of Athena, Annabeth was shown to be able to weave an owl patterned bridge to escape Arachne's spiders with no prior knowledge.
  
• Apollo's children are superior archers, healers, and musicians. They are additionally shown to be able to afflict others with curses such as rhymed speech due to their father's position as the god of poetry. In ancient times, many of Apollo's children were blessed with foresight. Some descendants of Apollo, like Halcyon Green, can interpret the will of the gods, while others like William Shakespeare have become famed poets.
  
• Like their father, children of Hephaestus are greatly skilled builders and craftsmen. Their talent as engineers are second to none and they can instinctively detect, identify, and operate any piece of machinery. In rare cases, they are blessed with the ability to create and control fire (which hasn't happened since 1666).
  
• Aphrodite's children are more attractive and have subtle powers compared to other demigods. With their mother being the goddess of beauty and love, they are natural experts in fashion and matchmaking with control over jewelry and makeup as well as skill in love magic. They also seem to have a greater clarity and sharper focus than most demigods. They have the same affinity for French, the language of love, as all demigods do for Greek. Some are also more interested in watching battles from the sidelines, rather than actually fighting. Some are even able to influence others with the strength of their voices using Charmspeak.
  
• Children of Hermes are more cunning and nimble than other demigods. Because Hermes is the god of dexterity, his children are considered to be very versatile in any skill. In particular they excel in athletics as well as business and thievery, being able to magically sense and pick locks.
  
• The powers of Dionysus' children are connected to those of Demeter's children. They promote the growth of vegetation (such as vines), especially wine grapes. Furthermore, they are able to both cause and cure insanity, as their father is the god of madness.
  
• Even though they do not have extraordinary powers, the children of Iris are exceptionally skilled as artists and communicators. Some children of Iris may be able to manipulate light or rainbows as Iris is the goddess of rainbows. Some, if not all, may be able to move at high speeds like Butch.
  
• The children of Hypnos are powerful yet underestimated demigods, possessing an intimate control and knowledge of their father's domain and the metaphysical world respectively.
  
• Nemesis' children have no known powers but they are loyal to allies and merciless to their enemies. Like their mother, they have a strong sense of justice and balance.
  
• Nike's children are highly competitive and intensely driven, causing them to excel as both athletes and fighters. They most probably win in things that rely on luck as their mother is the goddess of victory.
  
• Like Iris' children, Hebe's children do not have any incredible powers but they do possess a youthful appearance and are noted for being exceptional social workers.
  
• Although they can be random and unpredictable demigods, Tyche's children love games of chance. It is not advisable to bet against them as they have an uncanny ability of winning when it seems unlikely. They always seem to somehow always come out ahead. They have the power to manipulate luck.
  
• Hecate's children are powerful demigods and are the only demigods who can truly cast magic. They are able to utilize all ranges of magic, sorcery, and witchcraft. Some may have the power of necromancy and controlling the Mist.