Full list of all 93 Assassin's Creed Odyssey achievements. It takes around 80-100 hours to unlock all of the achievements in the base game on Windows.
The base game contains 50 achievements, and there are 5 DLC packs containing 43 achievements.
Complete all underwater location objectives.
Complete Xenia's questline.
Unveil all sub-regions of Greece.
Defeat all the Cultists of Kosmos.
Upgrade your Spear to Tier 6.
Complete Episode 9 + Epilogue.
Complete Episode 8.
Complete Episode 7.
Complete the Olympic questline.
Complete the Daughters of Artemis questline.
Become the first Mercenary.
Defeat the Cyclops.
Complete 20 Quests on Pephka, Obsidian and Abantis islands.
Upgrade the Adrestia to Legendary Status.
Defeat the Minotaur.
Defeat a Mercenary in the Arena.
Become Champion of the Arena.
Complete Markos's questline.
Defeat Medusa.
Reach Level 50.
Complete the Hippokrates questline.
Outwit the Sphinx.
Discover Atlantis and speak with Pythagoras.
Acquire a Tier 3 active Ability.
Sink your first Epic Ship.
Complete Episode 6.
Complete 20 Bounties, War Contracts, or Naval Quests from Message Boards.
Complete Episode 5.
Recover the Cyclops's eye from a goat on Kephallonia.
Equip a Legendary Armor set.
Defeat a full cluster of Cultists of Kosmos.
Perform an Overpower Attack with every weapon type.
Complete Episode 4.
Equip 1 Legendary melee weapon and 5 Legendary armor pieces.
Fully crew the Adrestia with Legendary Lieutenants.
Spend the night with another character.
Win your first on land conquest battle in any region (excluding Megaris in Hero's Journey).
Kill the Leader of any Region with Low Resources, other than Megaris.
Raise your Bounty to the maximum level.
Engrave a Legendary Item with a Legendary Effect.
Engrave your first item.
Complete Episode 3.
Complete Episode 2.
Upgrade the Adrestia for the first time.
Recruit and assign a Legendary NPC for your ship.
Acquire and equip your first Legendary item.
Cleave a ship while having an all-women crew.
Cleave a ship in half.
Complete Episode 1.
Complete the Battle of 300.
Heal by getting 10 headshot kills while you have the Golden Harbinger equipped.
Acquire the Sword of Kings
Secure your bloodline
Kill all the Ancients in the Order of Dominion in Messenia
Set 10 enemy ships on fire.
Heal by parrying 10 times with the Judgment of the Lion.
Continue the bloodline.
Kill all of the Ancients in the Order of the Storm in Achaia.
Discover the truth about Darius' past
Kill all the Ancients in the Order of the Hunters in Makedonia
Kill the Makedonian Lion
Land a Rush Assassinate that chains 4 times with the Blade of the Lion
Kill 10 enemies using the Rapid Fire ability.
Kill 10 enemies using the Fury of the Bloodline Ability.
Kill 10 enemies using the Death Veil ability
Complete Old Flames Burn Brighter
Complete Every Story Has an Ending
Complete One Really, Really Bad Day
Complete The Heir of Memories
Complete A Friend Worth Dying For
Complete The Show Must Go On.
Complete The Image of Faith
Complete A Poet's Legacy.
Complete Divine Intervention.
Complete A Brother's Seduction
Complete The Daughters of Lalaia
Defeat the Hekatonchires.
Kill 10 Isu Soldiers with the Blessing of Kronos enhancement.
Forge the 3 Legendary Weapons.
Completely fill the Knowledge Sequence.
Collect all the Keeper's Insights in Episode 3.
Dethrone the king.
Defeat all of the Fallen.
Close all Tartaros Rifts.
Collect all the Keeper's Insights in Episode 2.
Defeat Cerberos.
Win the conquest of Elysium with freed humans from the 3 main regions.
Remember who you are.
Kill all Overseers in Elysium.
Destroy all of the Marble Maiden Tributes.
Collect all the Keeper's Insights in Episode 1.
Defeat Arges, the Bright One
Defeat Steropes the Lightning Bringer.