Assassin's Creed Odyssey
93 Achievements
1,850
129-157h
One Head Down…
Defeat a full cluster of Cultists of Kosmos. Details for this achievement will be revealed once unlocked
30
20.88%
How to unlock the One Head Down… achievement in Assassin's Creed Odyssey - Definitive Guide
You can view the cult members from the main menu (far right tab, only shows up after making a little progress in the main story). From the cult menu you can keep track of which members you have killed and which still need to be killed (or discovered).
To unlock this achievement you need to kill a full cluster of Cultists of Kosmos. Each cluster contains six cultists and they will all need to be killed for the "The Cult Unmasked" achievement, so getting this one will come naturally if you're going for that one too. The first cluster you will likely unlock is the 'Eyes of Kosmos' cluster and includes the following cultists:
- Elpenor
- Sotera
- The Master
- Hermippos
- Midas
- Nyx the Shadow
You will solve the clues, or have the clues solved for you rather by completing certain story/side quests and it seems you cannot simply find and kill these at your convenience and they need to be discovered via the 'solving' of their clues, however solving of their clues is just finishing the right quest or looting the right body to find out who they are. Once you have killed all 6 cultists of any cluster, the achievement will unlock.