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