Question: why Astaros are inside Max?
Lore answer
Along time ago....
The war for the throne and balance always breaks out in both evil, good and neutrality
Amalthea, the goddess of life, wanted to create a heroic story, but Astaros, as the guardian of worldly balance, considered Amalthea's actions to be disruptive to the balance in both the story itself and Dimensional Path
The two of them have been sworn enemies for centuries, but Astaros could only watch the developments because a religion that was built made it difficult for him to move
Until one day the first hero appeared, Max Raiden.
The first of many heroes to fail, Max was the only one Astaros trusted after their meeting in the western mountains near the elf territory.
Astaros could feel the burden he was carrying and the confusion of being free, Astaros also saw the potential of the hero to fight Amalthea later so he made a pact with Max
Successor agreement, Max will be given long life and freedom so that his relationship is broken with Amalthea who reincarnated him
But as payment...Max must protect this world afterwards and become the new god for the world
That was the promise 100 years ago but Max still has to adapt as a human to use Astaros full abilites