Here is the full list of all 39 Achilles: Legends Untold achievements.
Finish the game with the Hero difficulty settings
Finish the game, not sparing any of the bosses when given the choice
Defeat 500 archers
Perform 50 counterattacks
Start a new game with New Game+
Defeat an enemy while having all possible negative statuses
Destroy all cursed masks
Send off all the soldiers’ souls
Get all the notes
Release all the prisoners from the cages
Finish the game as a human
Defeat Phobos
Unlock all the shrines
Open every runic chest
Find the hidden path
Defeat all the Laestrygonians
Unlock the armor with the Zeus theme
Defeat the Chimera
Visit every cellar and ruins available in the game
Upgrade your weapon or armor to the maximum level
Defeat Tydeus
Defeat the Minotaur
Defeat the bronze statue
See Hades in his true form
Survive the cultist ambush without receiving a negative curse status
Defeat Agamemnon
Unlock the armor with the scorpion theme
Defeat 20 opponents with a shield throw
Find the blacksmith
Kick your opponents 300 times
Destroy 1,000 destructible elements
Die for the first time. Get used to it.
Upgrade your weapon or armor for the first time
Purchase the first skill on the skill tree
Face Paris
Kill your first opponent
Defeat Paris
Finish the game as a hero
Finish the game, sparing all the bosses when given the choice