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