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