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