Hidden Content Guide#
Easter Eggs and Homages#
In-Game Easter Eggs#
| Easter Egg |
Location |
Description |
| Homage to the 300 Spartans |
Lakonia · Thermopylae |
Discover the ruins of the Battle of Thermopylae |
| Assassin’s Creed (2007) homage |
Delphi |
Fragments of Altair’s robe |
| Ubisoft Paris Easter egg |
Athens |
A hidden Ubisoft logo |
| Poseidon’s Wrath |
Specific Aegean Sea spots |
Special weather triggers undersea earthquakes |
| Cyclops cave murals |
Kephallonia |
Murals depicting the First Civilization |
| Atlantis ruins |
Keramikos seabed |
Fragments of ancient Atlantis |
Series Homages#
| Homage |
Location |
Source |
| Sea burial ritual |
Coastal regions everywhere |
AC4: Black Flag |
| Pieces of Eden |
Isu sites everywhere |
Core series lore |
| Altair’s book |
Delphi |
AC1/ACR |
| Hidden Blade prototype |
The first Hidden Blade quest |
Origins of the AC series |
| Assassin insignia |
Hidden walls |
The series emblem |
Hidden Locations#
Secret Caves#
| Cave |
Location |
Entry Requirement |
Treasure |
| Poseidon’s Cave |
Underwater Korinthia |
Dive in |
Legendary weapon |
| Isu Chamber |
Underground Attika |
|
|
| Lost Temple |
Lerna |
Unlocked after defeating the Hydra |
Legendary gear |
| Cave of the Moon |
Naxos |
Open at night |
Engraving recipes |
| Ancient Vault |
Antikythera |
Solve the mechanism puzzle |
Isu fragments |
Hidden Chests#
| Chest Type |
Location Trait |
Contents |
| Underwater bubble chest |
Where bubbles rise from the seabed |
Rare resources + gems |
| Torch chest |
Deep inside dark caves |
Legendary gear fragments |
| High chest |
Reach via parkour |
Engraving recipes |
| Concealed chest |
Hidden behind objects |
Advanced resources |
| Locked chest |
Requires a key |
Legendary weapon |
Hidden Quests#
Hidden Side Quests#
| Quest |
Trigger Condition |
Location |
Reward |
| The Lost Civilization |
Find every Isu fragment |
Delphi |
Isu ability upgrade |
| Trials of the Gods |
Talk to a specific NPC after level 50 |
Various |
God-tier gear |
| The Legendary Craftsman |
Collect every tablet |
Delphi |
Unique engraving recipes |
| Legacy of Atlas |
Complete the Atlantis DLC |
Atlantis |
Ultimate Isu gear |
| The Forgotten Heroes |
Defeat every Zeus Warrior |
Delphi |
Legendary mercenary title |
Hidden Dialogue Options#
| Dialogue |
Condition |
Effect |
| Specific NPCs’ hidden backstories |
Complete related side quests |
Unlocks extra information |
| Special lines with historical figures |
Reach specific levels |
Unique rewards |
| Secrets of the Cultists |
Hunt enough Cultists already |
Reveals more of the conspiracy |
First Civilization / Isu Ruins#
Isu Site List#
| # |
Site |
Location |
Level Requirement |
Contents |
| 1 |
Delphi Isu Chamber |
Phokis |
20+ |
Isu fragments + hologram |
| 2 |
Athens Isu Chamber |
Attika |
30+ |
Isu fragments + ancient documents |
| 3 |
Sparta Isu Chamber |
Lakonia |
35+ |
Isu fragments + weapon blueprints |
| 4 |
Atlantis ruins |
Keramikos seabed |
40+ |
Isu fragments + advanced gear |
| 5 |
Antikythera mechanism |
Antikythera |
50 |
Isu fragments + ultimate ability |
Isu Holograms#
| Hologram |
Location |
What It Reveals |
| Record of Creation |
Delphi |
The origins of the First Civilization |
| Record of the Flood |
Attika |
The great flood event |
| Record of Eden |
Sparta |
How the Apple of Eden was forged |
| Origins of Humanity |
Atlantis |
The creation of humankind |
| Doomsday Prophecy |
Antikythera |
The end of the First Civilization |
Underwater Secrets#
Underwater Caves and Ruins#
| Location |
Depth |
Treasure |
Notes |
| Kephallonia seabed |
Shallow |
Basic chests |
A beginner-friendly exploration area |
| Deep waters of Phokis |
Deep |
Isu fragments |
Requires diving skill |
| Cyclades seabed |
Medium |
Legendary gear |
Multiple shipwrecks |
| Keramikos sunken temple |
Deep |
Atlantis fragments |
An advanced challenge |
Underwater Exploration Tips#
| Tip |
Notes |
| Oxygen management |
Watch the oxygen bar and surface in time |
| Underwater combat |
Underwater you can only use daggers and bows |
| Bubble navigation |
Follow the bubbles to find treasure |
| Underwater map |
Synchronizing a Viewpoint displays underwater markers |
Hidden Cosmetics#
How to Unlock#
| Cosmetic |
Unlock Method |
Notes |
| Ancient Armor |
Complete every Isu site |
First Civilization-themed set |
| Armor of the Gods |
Defeat every mythical creature |
Mythology-themed set |
| Mask of Ares |
Complete every Spartan quest |
Ares-themed mask |
| Crown of the Sea |
Explore every shipwreck |
Ocean-themed set |
| Shadow Garb |
Complete every assassination quest |
Assassin-themed set |
| Crown of the Isu |
Complete every Isu site |
First Civilization set |
| Crown of Olympia |
Complete every Olympia quest |
Arena champion set |
Special Weather and Events#
| Event |
Trigger Condition |
Effect |
| Thunderstorm |
Random weather |
Enhanced visuals, special NPCs appear |
| Earthquake |
Random in specific regions |
Environmental destruction, hidden passages open |
| Solar eclipse |
Specific times |
Special lighting, Isu sites activate |
| Sea storm |
Random on the Aegean |
Harder naval combat, special chests |
More Hidden Chest Locations#
| Chest |
Location Description |
How to Get It |
| Sky chest |
Requires a Leap of Faith from a specific high point |
Find the highest point and jump |
| Underwater cave chest |
Deep inside a seabed cave |
Dive + find the cave entrance |
| Chest behind the mural |
Behind a false wall |
Attack the wall to reveal the hidden area |
| Chest behind the waterfall |
Behind the curtain of water |
Walk straight through the falls |
| Isu chamber chest |
Requires a specific key |
Complete a side quest to earn the key |
Detailed Easter Egg List#
| Easter Egg |
Location |
Details |
| Ubisoft logo |
A building somewhere in Athens |
Hidden in wall textures |
| 300 Spartans homage |
Thermopylae |
300 Spartan helmets lined up |
| AC1 Altair |
Delphi |
Hidden robe fragments |
| Underwater Atlantis |
Keramikos seabed |
Fragments of ancient ruins |
| Poseidon’s trident |
Specific waters |
A glowing trident on the seabed |
| Apple of Eden location |
Hidden cave |
Triggered by a specific quest |
| Secret |
Related Achievement |
How to Unlock |
| Hidden engraving recipes |
Ainigmata Ostraka Collector |
Solve all 22 tablet riddles |
| Cult secret chamber |
The End of the Cult |
Eliminate all 25 members |
| Ultimate Isu chest |
Isu Legacy |
Collect all 25 fragments |
| Deep-sea secret cave |
Deep-Sea Explorer |
Explore every shipwreck |
Hidden Dialogue and Interactions#
| Interaction Type |
How to Trigger |
Effect |
| Special NPC dialogue |
Complete specific side quests |
Unlocks hidden information |
| Ancient tablet interaction |
Use the Isu spear |
Triggers a hologram |
| Weather-triggered events |
Explore during a thunderstorm |
Special environmental changes |
| Time-triggered events |
Specific times of day |
NPCs appear |
Hidden Location Reference#
| Location |
Region |
How to Enter |
Contents |
| Poseidon’s Cave |
Korinthia seabed |
Diving |
Legendary chest |
| Isu power chamber |
Underground Attika |
Quest entrance |
Isu fragments |
| Lost Temple |
Cyclades seabed |
Diving |
Atlantis fragments |
| Craftsman’s chamber |
Mountains of Lakonia |
Climbing |
Engraving recipes |
Hidden Boss Trigger Conditions#
Mythical Creature Summoning Checklist#
| Creature |
Trigger Condition |
Location |
Suggested Level |
| Minotaur |
Complete the “Myths and Minotaurs” questline |
The lost labyrinth of Messara |
35+ |
| Medusa |
Complete the “Romantic Petrified Garden” questline |
Petrified Valley on Lesbos |
40+ |
| Sphinx |
Appears after the Oracle quest series |
The Atlantis entrance on Santorini |
45+ |
| Cyclops Brontes |
Complete the “Cyclops” quest |
Volcano crater on Andros |
32+ |
| Cyclops Arges |
Complete the “Bright Eyes” quest |
The volcano on Nisyros |
35+ |
Legendary Animals from the Hunt Questline#
| Animal |
Location |
Drop |
Notes |
| Kalydonian Boar |
Northern Boeotia swamps |
Unique leather material |
Counter its charge with fire weapons |
| Erymanthian Boar |
Arcadia highlands |
Unique materials |
It summons companions to flank you |
| Kretan Bull |
Near the Messara Arena |
Unique materials |
Watch out for its charging path |
Hidden Cultist Clues#
Members You Cannot Track Directly#
| Member |
How to Unlock |
Clue Source |
| Peloponnesian League branch leader |
Complete the Spartan storyline |
Spartan city notice board |
| Delian League higher-ups |
Hunt five Delian League members |
Cult torn pages |
| Heroes of the Cult leader |
Complete every Bloodline quest |
Mycenae tomb murals |
| Arena champion |
Win the Arena’s top challenge |
Arena notice board |
Collecting Cult Torn Pages#
| Page |
Location |
Purpose |
| Heroes of the Cult page |
Forts across the Peloponnese |
Pins down two members’ locations |
| Delian League page |
Eastern Aegean islands |
Pins down the Delian League higher-ups |
| Eyes of Kosmos page |
Athens and Sparta markets |
Reveals the Eyes’ identities |
DLC Hidden Content#
Legacy of the First Blade#
| Content |
Trigger Condition |
Reward |
| Persian Assassin keepsake |
Complete chapter one of the main story |
Legendary weapon blueprint |
| Darius’s Mask |
Complete every chapter |
Unique appearance |
| Persian courier passages |
Investigate in Makedonia |
Hidden chests |
Fate of Atlantis#
| Content |
Trigger Condition |
Reward |
| Trials of the three realms |
Complete each realm’s story |
Isu ability upgrades |
| Gates of Erebus |
Collect the Underworld keys |
Hidden legendary gear |
| Poseidon’s Seal |
Complete the Elysium challenges |
Poseidon set pieces |
Hidden Achievement Trigger Details#
| Achievement |
Trigger Details |
Commonly Missed Spot |
| Deep-Sea Explorer |
Explore every shipwreck marker |
Some wrecks are poorly marked in shallows |
| Isu Legacy |
Collect every Isu fragment |
Tomb bottoms are easy to overlook |
| The End of the Cult |
Eliminate every Cultist |
Two hidden members need clues unlocked first |
| Ainigmata Ostraka Collector |
Solve every tablet riddle |
The direction words in riddle verses are key |
Tip Many hidden items require specific conditions to trigger. After finishing the main story, revisit the regions you missed with a max-level character. Sweep every corner with Ikaros — it spots hidden objects the naked eye can’t. Exploration itself is the greatest reward!
Tip: Many hidden items require specific conditions to trigger. After clearing the main story, re-explore the regions you previously missed with a max-level character. Sweep every corner with Ikaros and you’ll find hidden objects the naked eye can’t perceive — exploration itself is the greatest reward!
Explore more in our Assassin’s Creed Odyssey hub.