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