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I am Alcyoneus, the bane of Pluto, the new master of Death!

–-Alcyoneus, to Percy, Frank, and Hazel, in The Son of Neptune.

Alcyoneus is one of the giants created by Gaea to destroy the gods. He is the giant equivalent to Hades/Pluto. Because of this, he is the eldest of the giants, since Hades is the eldest male Olympian.


The First Gigantomachy

Alcyoneus fighting Heracles.

He was the eldest and most prominent of the giants that attacked the gods. During the first Gigantomachy, Alcyoneus couldn't be killed as long as he was within his home territory, Pallene. During the war, Hercules fought him in battle (according to other stories, Hercules snuck up on him) and wounded him, but Hercules couldn't kill him until he dragged him out of Pallene using his great strength.

In the Series

In 1941, Gaea manipulated Hazel Levesque's mother Marie, into moving to Alaska, an area out of reach of the Olympian gods. Gaea would take control of Marie every night and force Hazel to call up precious stones and metals on a phantom island off the coast. Her powers almost lead to the rising of Alcyoneus until Hazel sacrificed herself to put the giant back in the earth and sink the island.

However, Hazel's sacrifice only delayed Alcyoneus' resurrection and he eventually reformed in the 1980s. Alycyoneus attacked a Roman legion that had gone up north to try and fulfill the Prophecy of Seven during the 1980s, but ultimately failed and lost the camp's sacred symbol, the Roman standard, an eagle staff that held the power of Jupiter.

The Heroes of Olympus

The Son of Neptune

Alcyoneus is first mentioned during a Senate meeting about the Quest to free Thanatos in Alaska. Alcyoneus is the one waiting for them and Hazel tells Reyna this (as Hazel was the one that helped raise him). When asked how she knew this, Nico interrupts saying that he was the one giant created to defeat their father, Pluto.

Hazel and Arion, his slayers

Hazel Levesque, Percy Jackson, and Frank Zhang travel north to Alaska to rescue Thanatos, whom the giant has chained. They arrive at his ice fortress with the help of Arion. Hazel and Arion try and defeat the giant while Frank frees Thanatos and Percy fights an army of shades who use to be the soldiers Alcyoneus defeated. After freeing Thanatos, Frank joins the fight against the giant and saves Hazel by transforming into a bird and pecking at his eyes. Frank, Hazel, and Arion manage to defeat him, but can't kill him as long as he is in Alaska, so Frank used a rope to pull Alcyoneus ten miles into Canada with the help of Arion. Alcyoneus insults them at first, claiming he can't be killed in his territory until Frank informs him that he is no longer in his territory, but they are in Canada. Alcyoneus tried to run back to Alaska, but is stopped when Frank turns into an elephant and pushes him back, and he is eventually defeated by Arion and Hazel who decapitates the giant, turning him into a pile of very expensive rocks.

The Mark of Athena

After Percy remarks that they need the gods' help to kill the Giants, Jason remembers how Frank and Hazel had killed a giant without a god's help. Frank explains that Alcyoneus was a special case as he was only immortal in the territory in which he was reborn - Alaska and not Canada where they had dragged him. While Frank wishes that they could kill all of the giants the same way, they will need the gods help for the rest of them.

The House of Hades

It is mentioned by Hyperion and Krios, who are guarding the Doors of Death, that all the giants who were killed have reformed and returned to the mortal world through the Doors of Death, including Alcyoneus.

The Blood of Olympus

While Alcyoneus isn't ever mentioned by name, he is among the giants assembled in the Athenian Acropolis as seen in Piper's dream. He fights the Seven Heroes of Olympus in the final battle of the Second Gigantomachy, and is ultimately brought down and killed by the combined efforts of Hazel, Arion, and Hades (invisible with his Helm of Darkness), after which the Lord of the Dead opens up an abyss under the fallen giant's body, sending Alcyoneus back to Tartarus.


Alcyoneus is described in The Son of Neptune as being bigger than Polybotes, being over 40 feet tall, though still slightly shorter than Porphyrion. His skin looks like it is made of a metallic gold-like material. His legs however are rust colored dragon legs. His armor is made of platinum links and he has an iron staff the size of a totem pole. Being made from precious stones and metals, his body is covered in them, including stones in his red braided hair. Unlike other immortal beings who bleed ichor, Alcyoneus's blood is made from oil and it is said raw diamonds make up his heart. When Arion pulls him from Alaska, his golden skin became the color of brass.


Gaea, his mother

As the eldest giant, and opposite of Hades/Pluto, Alcyoneus is one of the three most powerful giants (along with Porphyrion and Polybotes). Not much is known about the true extent of Alcyoneus's power:

  • Prowess in Battle: Even for a giant, Alcyoneus has enhanced strength, and is one of the best warriors among the giants. In the first Gigantomachy, he was able to fight mighty Hades himself along with Hercules, though he was eventually defeated when Hercules carried him out of his native territory. In The Son of Neptune, he was able to fight Hazel and Arion simultaneously, with their supersonic speed being the only thing that kept them alive in the confrontation. He is ultimately defeated, however, when Frank joins the fight, with his shape-shifting catching Alcyoneus off-guard. Alcyoneus is defeated once again in The Blood of Olympus by the combined efforts of Hazel, Arion, and Hades. Alcyoneus is also very skilled with a staff, managing to fend off Hazel and Arion for a time, even when they were traveling at supersonic speeds.
  • Shade Control: Alcyoneus also controls shades, ghostly warriors made up of members of the old Fifth Cohort. After death, they had sided with Gaea, in hopes of getting a second chance of life and were under the control of her eldest giant son.
    • Soul Sensing: After he woke up in The Son of Neptune when he was dragged out of Alaska, he smelled the air, and sensed souls were sniffed out.
  • Giant Invincibility: Unlike any of the other giants, Alcyoneus's strongest ability is that he won't die as long as he is in his territory (Pallene before the series and Alaska in The Son of Neptune). Hence, no matter how badly damaged he is, he will simply reform. However, once dragged out of his home territory he can be killed by any means. He was defeated when Hercules single handedly defeated and carried him out of his territory. After he was dragged to Canada, Hazel decapitated him. In The Blood of Olympus, he was apparently reformed and then killed a second time by the combined efforts of Hazel, Arion, and Hades (invisible with his Helm of Darkness) when the Lord of the Dead opens up an abyss under the fallen giant's body, sending Alcyoneus back to Tartarus.


Hercules, the demigod who killed him the first time.

  • Alcyoneus is the only giant that can be killed without the help of a god, as long as he is outside his territory.
  • Alcyoneus is the only immortal who does not bleed ichor; he instead bleeds oil, as his body is made from the riches of the Underworld.
  • Despite being the bane of Pluto, Alcyoneus's body is made of the riches of the Underworld, meaning his entire body is made of something under Pluto's realm of power.
  • Hazel mistakenly mentions that Gaea forced her to raise Porphyrion when she lived in Alaska, when she actually raised Alcyoneus.
The Heroes of Olympus
Core Series: The Lost Hero | The Son of Neptune | The Mark of Athena | The House of Hades | The Blood of Olympus
Main Characters: Jason Grace | Piper McLean | Leo Valdez | Percy Jackson | Frank Zhang | Hazel Levesque | Annabeth Chase | Reyna Ramírez-Arellano | Nico di Angelo | Gleeson Hedge
Secondary Characters: Hylla Ramírez-Arellano | Dakota | Tyson | Ella | Octavian | Halcyon Green | Dr. Howard Claymore | Alabaster C. Torrington | Lamia | Iapetus/Bob
Minor Characters: Rachel Elizabeth Dare | Grover Underwood | Thalia Grace | Fleecy | Mrs. O'Leary | Kinzie | Arion | Calypso | Lou Ellen Blackstone | Chiron | Will Solace | Tristan McLean | Don | Julia | Jacob | Michael Varus | Burly Black | Medea | Midas | Lityerses | Phineas | Otrera | Echo | Narcissus | Sciron | Pasiphaë
Olympian Gods: Zeus | Hera | Poseidon | Hades | Ares | Demeter | Athena | Apollo | Artemis | Hephaestus | Aphrodite | Hermes | Dionysus
Minor Gods: Achelous | Aeolus | Asclepius | Boreas | Eurus | Hecate | Iris | Hypnos | Keto | Khione | Kymopoleia | Mithras | Nemesis | Nike | Notus | Phorcys | Serapis | Thanatos | Triptolemus | Zephyros
Roman Gods: Jupiter | Juno | Neptune | Pluto | Mars | Minerva | Ceres | Lupa | Bellona | Fortuna | Janus | Terminus | Vulcan | Mercury | Apollo (Roman) | Diana | Venus | Bacchus | Pomona | Aquilon | Hercules | Cupid | Auster | Favonius | Letus | Victoria
Giants: Enceladus | Porphyrion | Alcyoneus | Polybotes | Ephialtes | Otis | Damasen | Clytius | Mimas | Orion | Hippolytos | Thoon | Periboia
Undead: Gray | Zombie
Primordial Gods: Gaea | Tartarus | Ourae | Nyx | Chaos | Ouranos | Akhlys | Hemera | Elpis | Spes
Monsters and Magical Creatures: Cynocephali | Gorgon | Gryphon | Harpy | Basilisk | Lycanthrope | Gegeines | Cyclops | Katobleps | Unicorn | Giant Eagle | Ichthyocentaur | Satyr/Faun | Storm Spirit | Laistrygonian Giant | Lares
Related Content: Rick Riordan | Haley Riordan | Percy Jackson and the Olympians | Percy Jackson and the Olympians: The Ultimate Guide | The Demigod Files | The Demigod Diaries | The Son of Sobek | The Singer of Apollo | The Staff of Serapis | Percy Jackson's Greek Gods | Percy Jackson's Greek Heroes | The Crown of Ptolemy | Demigods & Magicians | Demigods of Olympus | Percy Jackson Demigod Collection
Species: Arai | Blemmyae | Basilisks | Centaur | Cyclopes | Dragon | Drakon | Empousai | Fire-Breathing Horse | Gegeines | Gemini | Ghoul | Giant | Gorgon | Harpy | Hekatonkheire | Hippalektryon | Hippocampus | Hyperborean Giant | Ichthyocentaur | Karpoi | Katobleps | Keres | Laistrygonian Giant | Lycanthrope | Makhai | Merperson | Myrmekes | Nikai | Nymph | Pegasus | Satyr | Stymphalian Birds | Telekhine | Scythian Dracaena | Siren | Unicorns | Venti | Yales
Friendly Monsters: Argus | Blackjack | Briares | Bombilo | Chiron | Cottus | Don | Ella | Festus | Gleeson Hedge | Gray | Grover Underwood | Guido | Gyges | Lysas | Mellie | Mrs. O'Leary | Ophiotaurus | Peaches | Peleus | Porkpie | Rainbow | Scipio | Tyson | Tempest | Sssssarah
Enemy Monsters: Antaeus | Agrius and Oreius | Arachne | Cacus | Carthaginian Serpent | Charybdis and Scylla | Chimera | Chrysaor | Clazmonian Sow | Colchis Bulls | Echidna | Euryale | Geryon | Joe Bob | Kampê | Kekrops | Ladon | Lamia | Manticore | Medusa | Minotaur | Nanette | Nemean Lion | Polyphemus | Python | Sphinx | Stheno | Typhon | Trojan Sea Monster
Neutral Monsters: Carnivorous Sheep | Cerberus | Erymanthian Boar | Gray Sisters | Flesh-Eating Horse | Furies | Gryphon | Orthus | Skolopendra | Sybaris