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