|Appearances||The Last Olympian|
Morrain accompanied an Empousa, Ethan Nakamura, and Prometheus to a meeting with Percy Jackson in which he carried the white flag. Though he is feared by Percy he is also pitied by him, as his attention span is shown to be short, his intelligence even smaller, and his only words to be spoken are "Uh oh". He reminds Percy of Tyson and his childish ways. At the end of the meeting Prometheus calls his name and the group departed back for battle. It is unknown if Morrain participated in the Battle of Manhattan or if he survived the conflict without being sent to Tartarus.
Morrain is massive (about 30 feet tall) with blue skin, colorless hair, and bright blue eyes. Huge carnival prize animals hang around his waist.
Morrain's character appears to be based on no mythological background other than him being a Hyperborean giant. He appears in only one scene in one book with only minimal speaking parts and no major accomplishments credited to his behalf. His name is only said once by Prometheus in the entire story and he is possibly the character that from all of the books we know the least about. All of these background traits make him similar to Queen Sess. Some fans believe that Morrain is meant to be the large Hyperborean that Percy helps Annabeth take down shortly after the meeting. There is no factual evidence to support this, so as far as we know Morrain's future after the meeting is unknown.
|Species:||Centaur | Cyclopes | Dragon | Drakon | Empousa | Giants | Harpy | Hyperborean Giant | Ichthyocentaur | Karpoi | Laistrygonian Giant | Pegasus | Skolopendra | Stymphalian Birds | Telekhine|
|Friendly Monsters:||Argus | Blackjack | Briares | Chiron | Don | Ella | Festus | Gleeson Hedge | Grover Underwood | Hippocampus | Mellie | Mrs. O'Leary | Ophiotaurus | Peleus | Scipio | Tyson | Tempest|
|Enemy Monsters:||Agrius and Oreius | Arachne | Basilisk | Charybdis and Scylla | Chimera | Chrysaor | Clazmonian Sow | Colchis Bull | Echidna | Euryale | Geryon | Joe Bob | Kampê | Manticore | Medusa | Minotaur | Nemean Lion | Polyphemus | Sphinx | Stheno | Typhon ||
|Neutral Monsters:||Cerberus | Erymanthian Boar | Gray Sisters | Gorgons | Furies | Flesh-Eating Horse | Gryphon | Hippocampus | Siren|