The dev team of Assassin’s Creed Odyssey explained that the mythical creatures the appear in Assassin’s Creed Odyssey are actually human beings who were corrupted by the Pieces of Eden, such as the Medusa and the Minotaur, and if that Piece of Eden falls into the hands of others, they will find themselves “transforming” into mythical creatures, similarly to how Legeia, Bryce’s lover, transformed into Medusa upon taking the Apple of Eden found in the First Civilization site, showcased during the Gamescom demo.

The above statement could implies that among the previously unknown abilities of the Apple of Eden (or at least one/some of them) (Juno once shed light on the fact that the Pieces of Eden had abilities which they previous did not known about) is to affect its wielder on a genetic level, leading to these mutations. Another theory is that since after defeating the creature, no body for the original is found, the Apple might be entirely using up the energy and the matter on the body of its wielder and creating a force field in the shape of the creature, similarly to how in Assassin’s Creed III, Juno once said that if several people are subjected to the beam of the Apple of Eden and they all thought of one thing, like “tree”, the Apple will create a tree.

The Isu / First Civilization site explorable during the Gamescom demo is somehow connected to Layla’s adventure in the present day segment of the game.

Horodotus will be “enthralled” by the Broken Spear of Leonidas and accept to join the protagonist in their journey and document their odyssey.

The protagonist will track down several cultists of the Cult of Kosmos and upon defeating them, will acquire “shard” which they’ll use to enhance the Broken Spear of Leonidas in a “forge”. It must be noted that in the Game Informer cover story, it was revealed that the protagonist will be able to upgrade the Spear in First Civilization “shrines”.

Unlike Assassin’s Creed Origins, Odyssey will explain the connection between the protagonist (Alexios/Kassandra) and their eagle Ikaros.

Assassin’s Creed Odyssey will feature over 300 quests and about 600 points of interest, and that includes areas that the player can find, explore and interact with.

The Daughters of Artemis faction will be a “gateway” to defeating legendary creatures/animals in the Odyssey.

Supporting characters will refuse to join the protagonist on their ship, the Adrestia, if the had a bad reputation/committing atrocious acts against the people. However, players will come across a quest in the game where they encounter a pirate. In that quest, the protagonist will use the sails and figurehead of the Adrestia to raise his/her reputation among the people.

At the beginning of the experience, the protagonist will only be dressed in sandals and undergarments.

Elements such as the floating ashes in the Medusa First Civilization site are unique to their own setting, and those temples/values are handcrafted and their atmosphere isn’t reused in elsewhere in the game.

The dev team decided not to give the protagonist a shield to make the experience more challenging.

Assassin’s Creed Odyssey implements a system for the mercenaries (the law enforcement system in the game) that they don’t simply spawn when needed, they’re always around and will engage with the protagonist when they commit any crimes, whether towards them or any of the citizens, such as stealing, killing, destroying property..etc.

The rationale behind making an Assassin’s Creed game that predates what is known today as the Assassins and Templars, is that ideologies predate the names of organizations, similarly to how players have been playing football long before the NFL.