Here is the full list of all 30 Apotheon achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Beat game on Olympian Difficulty
Find all lockboxes on Olympus.
Root out the assassins in the Acropolis.
Access the sunken wreck of the Euphemia in the Sea.
Access the Gold Mine in the Sea.
Access the Symposium of the Sun in Apollo's hall.
Find all rare weapons on Olympus.
Access Apollo's nectar cellar.
Access the Hunter's Trove in the Forest.
Aquire the Cestus of Aphrodite.
Acquire the powers from all twelve Olympian Gods.
Access the Agora Armoury.
Access the Refugee stash in the Forest.
Access the Assassin Stash in the Swamps.
Aquire the Kantharos of Dionysus.
Acquire the Thunderbolt of Zeus
Access the Agora Market Scroll-keeper’s Office.
Aquire the Sandals of Hermes.
Aquire the Artifice of Hephaestus.
Acquire the Aegis of Athena
Access the Merchant Stockpile in the Acropolis.
Acquire the Crest of Ares
Access Kleio's gift in the Acropolis.
Meet the Necromancer in Hades.
Acquire the Trident of Poseidon
Acquire the Sheaf of Demeter
Acquire the Bow of Artemis
Access the Secret Grove at the Shrine of the Nymphs.
Acquire the Lyre of Apollo
Ascend to Mount Olympus