Fatal Flaw

A fatal flaw is a flaw in Half-Bloods and just about anybody(humans and demigods). These can often be the downfall of an given Half-Blood, or anybody for that matter. The topic of fatal flaws first shows up in The Sea of Monsters after Annabeth dove overboard because of Siren's music. She thinks she can fix Luke and bring her mother and father back together, essentially. This is due to her fatal flaw, hubris. She then explains to Percy about fatal flaws and the topic appears over the rest of the series. Percy's flaw (see Known Fatal Flaws) is said by Athena to be a dangerous flaw for the hero of the Great Prophecy, possibly because it means he would "sacrifice the world" to save someone he really cares about.

The Siren's music has an oral hypnotic effect. The belief is that the Sirens sing about the fatal flaws of anyone who hears their song(it is not confirmed). Certain flaws, such as hubris, can produce an enticing image which is what lures sailors and adventurers to their deaths, either by drowning or by being eaten by the Sirens.

Known Fatal Flaws

 * Percy Jackson's fatal flaw is excessive personal loyalty. He will risk his live for anyone: his friends, family, strangers, and even his enemies.
 * Annabeth Chase's fatal flaw is hubris. She thinks she can do anything better than even the gods such as saving her family (seen in The Sea of Monsters where she jumped overboard from the Queen's Revenge to hear the Siren's deadly music).
 * Nico di Angelo's fatal flaw is holding grudges. He will hold a grudge even if it costs his own life. In The Battle of the Labyrinth, his deceased sister, Bianca, tells him that holding grudges are very dangerous for the children of Hades.
 * Thalia Grace's fatal flaw is lust for power. She desires power even though she knows she does not need it.
 * Clarisse La Rue's fatal flaw is either hubris (she thinks she is better than everyone) or vanity (she has excessive pride about her skills in battle).
 * Jason Grace's fatal flaw is also, like Percy, excessive personal loyalty. He will risk his life for anyone he cares about. It also may be a lusr for power as he is a child of Jupiter/Zeus and his sister and father both want power.
 * Leo Valdez's fatal flaw is his feelings of inferiority, thinking that he has to prove himself constantly and that he is lesser than anyone else (for example Jason Grace).
 * Piper McLean's fatal flaw might also be excessive loyalty, like Percy Jackson. It is hinted that the children of Aphrodite will do anything to protect someone they love.It might also be hubris as she tried to charmspeak Jason back to life even though it was supposed to be impossible.