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