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Bessie? But… he’s too cute. He couldn’t destroy the world.

Percy Jackson in, The Titan's Curse.

The Ophiotaurus (meaning Serpent Bull) was an ancient monster that could bring down the gods if it was slain and its entrails burnt. It was a half-cow, half-serpent creature. It was nicknamed Bessie by Percy Jackson, who initially assumed it was female. The Ophiotaurus is currently safe in an aquarium in Olympus built by Hephaestus.


In the ancient myth, it is said that the creature emerged from chaos with Gaea and Ouranos. It was slain by an ally of the Titans during the first Titanomachy, but its entrails were retrieved by Zeus' eagle before they were burned.

Afterwards, the gods kept it in heavens in the combined constellation of Taurus and Cetus.

Percy Jackson and the Olympians

The Titan's Curse

The Ophiotaurus was the creature that Artemis attempted to kill before it could turn to the Titans' side and defeat the gods. Percy first meets him trapped in a net and, being unaware that the creature was actually a male, nicknames him Bessie. Thanks to the Hippocampi and Percy the monster was freed. The Ophiotaurus was the center of the General's plan to bring down the gods by having Thalia Grace call the beast to her, kill it, then sacrifice its entrails as a tribute. However it was Percy, not Thalia, that the Ophiotaurus follows around. This is due to Percy's rescue, and the monster's belief that Percy is its protector. Grover later takes it to Olympus, and Percy sacrifices the Nemean Lion's Pelt to ensure they arrive safely. Deciding to allow it to live after a heart filled testimony by Percy, Poseidon and Hephaestus made a sphere-shaped aquarium for it on Mount Olympus, after Zeus refuses to let Poseidon harbor him under the sea as a "bargaining chip."

Percy Jackson, the one who took care of the Ophiotaurus and named him Bessie.


The Last Olympian

Percy sees him in his aquarium during the Battle of Manhattan when he goes into the Hall of the Gods. He tries to remain out of Kronos' notice, and gets out of the conflict alive.


  • He was nicknamed Bessie by Percy Jackson.
  • He is the first monster to be presumed as the opposite gender, the second being Ammit the Devourer, by Sadie.
  • If the Ophiotaurus' entrails are burned or sacrificed, they slayer would gain the power to defeat the gods.
Percy Jackson and the Olympians
Core Series: The Lightning Thief | The Sea of Monsters | The Titan's Curse | The Battle of the Labyrinth | The Last Olympian
Main Characters: Percy Jackson | Grover Underwood | Annabeth Chase | Tyson | Clarisse La Rue | Thalia Grace | Nico di Angelo | Chiron | Luke Castellan | Rachel Elizabeth Dare
Secondary Characters: Sally Jackson | Travis Stoll | Connor Stoll | Mrs. O'Leary | Silena Beauregard | Charles Beckendorf | Paul Blofis | Blackjack | Zoë Nightshade | Bianca di Angelo | Juniper | Ethan Nakamura
Minor Characters: Gabe Ugliano | Frederick Chase | Michael Yew | May Castellan | Austin Lake | Kayla Knowles | Maria di Angelo | Will Solace
Olympian Gods: Zeus | Hera | Poseidon | Demeter | Ares | Athena | Apollo | Artemis | Hephaestus | Aphrodite | Hermes | Dionysus | Hades | Hestia
Minor Gods: Amphitrite | Ariadne | Hecate | Iris | Janus | Morpheus | Nemesis | Pan | Persephone | Triton
Titans: Kronos | Atlas | Calypso | Iapetus | Krios | Hyperion | Oceanus | Prometheus
Related Content: Rick Riordan | The Lightning Thief (film) | Sea of Monsters (film) | The Demigod Files | Demigods and Monsters | The Ultimate Guide | The Heroes of Olympus | The Trials of Apollo | Disney+ Series
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