Percy Jackson and the Olympians (often referred to as just Percy Jackson) is a fantasy series by Rick Riordan. The series consists of two main series, Percy Jackson and the Olympians (The Lightning Thief, The Sea of Monsters, The Titan's Curse, The Battle of the Labyrinth and The Last Olympian) and The Heroes of Olympus (The Lost Hero, The Son of Neptune, The Mark of Athena, The House of Hades and The Blood of Olympus) as well as several spinoff titles, such as databooks and graphic novels. Two movies have been made from the first two books, and video games based off those movies have been made.
The Kane Kronicles also takes place within the same universe, and several crossover stories confirm this. Magnus Chase and the Gods of Asgard is also set in the same universe.
The premise is that the Ancient Greek Gods moved to America in modern times and continue making demigods (or half bloods) and follows the adventures of the titular Percy Jackson, the son of Poseidon.
The Riordanverse is a very formidable verse, with the Major Olympian Gods having casual Tier 6 feats (throwing mountains or islands; drowning the entire planet; fighting with the Titans, which vaporized the Mediterranean Sea or having divine control over their respective domain, like the atmosphere) and even Tier 5 feats (like Artemis, for creating a constellation). Even their weapons, like Zeus Master Bolt is powerful enough to "makes mortal hydrogen bombs look like firecrackers". With this kind of power comes a standard set of abilities that every major god has, like: Superhuman Physical Characteristics, Immortality (Types 1, 4 and 8), Shapeshifting, Animal Manipulation, Mind Manipulation, Transmutation, Teleportation, Curse Manipulation, Intangibility, Healing, Smite Summoning, Telepathy, Cosmic Awareness and Supernatural Sight, Size Manipulation, Flight, Can exist in many places at once and of course their individual abilities (like Water Manipulation for Poseidon). Titans and Giants can be scaled to them, since they are comparable in power. Primordial gods, also called Protogenos are even more powerful and are listed as Planet level (Since they are essentially sentient aspects of the universe itself, such as Gaia being the very planet itself).
The offspring of gods are called Demigods or Half-Bloods, which are half-mortal, half-god. They are of course not near as powerful as their parents, but powerful demigods like Percy Jackson or Jason Grace have shown several Tier 7 feats (Destroying parts of the Hubbard Glacier or creating a volcanic eruption) and even fought with powerful beings like Hyperion, Krios or various giants themselves (although they were all at a weakened state). They are comparable to Hazel Levesque, who was able to destroy a small island, which scales to the strongest three children (Poseidon, Hades, Zeus) as Island level.
The Egyptian Gods are almost comparable to the Greek/Roman Gods and also possess Tier 6 feats; like Set (one of the strongest gods); who created the Sahara desert; could turn all of North America into a desert and create planetary storms at full power. The supreme beings of this pantheon like Ra or Apophis are furthermore listed as Planet level for creating the world or being able to destroy it. Magicians like Carter Kane, who are the counterpart to the Demigods, are comparable to them in terms of power with Carter Kane being able to fight Percy Jackson (one of the strongest demigods) to a stalemate.
The Norse Gods are also quite powerful, and comparable to the other Pantheons in the Verse. Odin is responsible for creating 7 of the 9 worlds from Ymir's corpse alongside his brothers Vili and Ve, the Midgard Serpent coils around the whole planet, and Fenriswolf and Surtr and prophecized to devour the sun and moon and burn the whole world to ash at Ragnarok, respectively.
Supporters and Opponents of the Series
Sword of Hades
Sword of summer
Ra's croock and flail