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