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Genshin Impact

Cassiodor Story and Profile

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Genshin Impact Cassiodor Story and Profile.png

Cassiodor in Genshin Impact is the Harmost of Remus Sebastos, who's known to the Traveler as Monsieur Os. Check out Cassiodor's story and lore, along with his in-game quest appearances here in this lore guide!

List of Contents

Cassiodor Character Information

Cassiodor Character Profile

Cassiodor
Genshin - Cassiodor Nation: Fontaine
Element: N/A
Faction: Remuria

Cassiodor Story and Lore

Harmost of Remus Sebastos

Genshin Impact Cassiodor Story and Profile - Harmost of Remus Sebastos.png

Cassiodor was originally a Harmost of Remus Sebastos, a person capable of rewriting the musical score of the Phobos. He holds the same position as Boethius, the traitor to the people of Remuria who seized control of Chaotic Symphony.

Cassiodor is also the Harmost the Traveler was seen conversing with, each time he dreams as the Imperator himself.

Turned Into Monsieur Os

Genshin Impact Cassiodor Story and Profile - Turned Into Monsieur Os.png

Because of the Chaotic Symphony, Cassiodor's soul inhabited a cat who first referred to himself as Ouranides of Ouranopolis, or Osse. Only when Osse spoke to Boethius during the Underwater Nocturne, has he gained his moniker, Cassiodor, once more.

Sacrificed Himself to Destroy Phobos

Genshin Impact Cassiodor Story and Profile - Sacrificed Himself to Destroy Phobos.png

In the Domus Aureus, Cassiodor assimilated with the Phobos, thereby filling it with his desire to end its reign. And with the help of Traveler to deal the finishing blow, the Phobos, along the remnants of Remuria, were freed, and granted entrance to the Great Sea.

Cassiodor In-Game Mentions & Appearances

Canticles of Harmony Quest Line

Quest Name Type
Shadow Over Petrichor World Quest
Underwater Nocturne World Quest
The Last Day of Remuria World Quest
Gradus ad Capitolium World Quest
Fortune Plango Vulnera World Quest

Genshin Impact Related Guides

Non-Playable Characters

Gods and Creatures

Gods and Creatures
Genshin - Paimon Paimon Genshin - Kichiboushi IconKichiboushi Genshin - Shiki Taishou IconShiki Taishou
Genshin - Naberius Naberius Genshin - Ronova Ronova Genshin - Istaroth Istaroth
Genshin - Asmoday Asmoday Genshin - Rukkhadevata Rukkhadevata Genshin - Deshret Deshret
Genshin Impact - EnjouEnjou Genshin - TsumiTsumi Genshin Impact - BosaciusBosacius
Genshin Impact - IndariasIndarias Genshin Impact - MenogiasMenogias Genshin Impact - BonanusBonanus
Genshin - Takuya IconTakuya Genshin - Guizhong God of Dust Haagentus Guizhong Genshin - Hanyuuda Chizuru Hanyuuda Chizuru
Genshin - Lord Kamai Kamai Kenji Genshin - Madame Ping - Streetward RamblerMadame Ping Genshin - Sea GazerSea Gazer
Genshin - CaribertCaribert Genshin - Bongo-HeadBongo-Head Genshin - ElynasElynas
Genshin - IdyiaIdyia Genshin Impact - FerdinandFerdinand Genshin - MamereMamere
Genshin - EgeriaEgeria Genshin - CallirhoeCallirhoe Genshin - SurtalogiSurtalogi
Genshin - LingyuanLingyuan Genshin - FujinFujin Genshin - HerblordHerblord
Genshin - Mountain ShaperMountain Shaper Genshin - Moon CarverMoon Carver Genshin - YuandaiYuandai
Genshin - PhobosPhobos Genshin - CassiodorCassiodor Genshin - WolfyWolfy
Genshin - Ajaw Ajaw Genshin - DurinDurin Genshin - Yohualtecuhtin Yohualtecuhtin
Genshin - Cocouik Cocouik Genshin - Haden Haden Genshin - Kukulkan Kukulkan
Genshin - Sebas IconSebas Genshin - Nibelung Icon Nibelung

Human NPCs

Human NPCs
Genshin - La Signora IconLa Signora Genshin Impact - KazuhaKazuha's Friend Genshin Impact - HalfdanHalfdan
Genshin Impact - KatarinaKatarina Genshin - ZhiqiongZhiqiong Genshin - Liben the Traveling MerchantLiben
Genshin Impact - BoyangBoyang Genshin - RongzhaoRongzhao Genshin - RanaRana
Genshin - DunyarzadDunyarzad Genshin - Elchingen Elchingen Genshin - Haniyyah Haniyyah
Genshin - JehtJeht Genshin - Babel Babel Genshin - Babel Azariq
Genshin - Aderfi Aderfi Genshin - Dvorak Dvorak Genshin - Soraya Soraya
Genshin - EideEide Genshin - ScarlettScarlett Genshin - TimaeusTimaeus
Genshin - YingYing'er Genshin - VacherVacher Genshin - CrucabenaCrucabena
Genshin - ClervieClervie Genshin - PeruerePeruere Genshin - SabbahSabbah
Genshin - AffanAffan Genshin - VedrfolnirVedrfolnir Genshin - HroptatyrHroptatyr
Genshin - Vinster King Vinster King Genshin - AtossaAtossa Genshin - Tholindis, Tholindis
Genshin - Chuychu Chuychu Genshin - Guthred Guthred Genshin - Bona Bona
Genshin - Capitano the Captain Fatui Harbinger Capitano Genshin - Xbalanque Xbalanque Genshin - DireidythDireidyth
Genshin Impact - Aroni Aroni Genshin Impact - Macani Macani Genshin Impact - Pulonia Pulonia

Related Races and Species Guides

Significant Races and Species
Saurians Melusines
Youkai Heavenly Principles
Adepti Aranara

List of All Characters

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