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