So I beat the game for good and I thought that others would benefit from knowing how to access his story line.
In order to do so, you have to beat the game normally (Choice does not matter), then start up a new game + and play through the game to the branch. Then choose the other side of the story and complete said side. After that, start a new game ++ (You NEED to have 2 stars on your save file) and play to the branch. You will then get a choice to view Arioch's story. if you're too lazy, the details are in the spoiler box to read through. Arioch's story also has 3 extra dungeons including the true final boss.
Starts off on Fiora's side of the story
Eris reveals herself to York on the deserted island after Fiora leaves with Arioch
You fight Arioch at the shrine instead and Arioch reveals himself to be a clone of York.
Turns out Eris kept resetting time in the Sandbox world to save York from dying resulting in the multiple dead copies 0f York to build up and become Arioch.
Fiora gives up her life to be absorbed into the sword & Eris joins
Tower of heaven proceeds as normal but Arioch and York fight off the machines proclaiming that they will duel in the future
Realm of Imaginary numbers proceeds as if it was York's side of the story right up to the "final" boss.
After killing the "final" boss, Airoch demands a duel with York. York wins and uses Arioch to insert Fiora's soul into the angel system.
Olber and the Knights begin to move people to the promised land.
Soon, monsters attack the people in the promised land prompting York, Eris, and Ibis to travel to the promised land via the realm of imaginary numbers.
You learn that Eris is the daughter of the creator of the Angel system who entered to govern and protect the people of the Sandbox world to find the perfect human being to survive the curse.
Turns out the promised land is actually the Real world after the curse hit and it looks like s*it
You go to a village and help Olber fight off the monsters and protect the refugees
Eris suggests going to the tower of administration through a cave filled with icy floors.
So basically you go through the cave and climb the tower (Both of which are dungeons)
You find Arioch who informs you of the Angel system creating more monsters in reality. Arioch decides to turn himself into a sword that you can use to investigate the interface dimension.
Which is also the REAL final dungeon. be careful of the trap floors but if you have all 3 characters with an Original soul equipped, you can just AUTO through the fights.
You reach the end to find Eris' father turned into a monster.
Eris' father actually created and started the curse in order to force his plan for the ultimate evolution of humanity upon the earth.
He calls his daughter and her friends failures and proceeds to get his ass kicked by the party
Fiora intervenes at the end as a soul that was trapped into the Angel system's body thus forcing the system to self destruct taking the Father down with him.
You manage to save Fiora's soul by attacking the angel system with Arioch's sword. however, the sword only has room for 1 soul and thus Arioch deletes himself in order to make sure Fiora stays in the sword killing him off for good.
Some time afterwards, All of the people have left the sandbox world and began rebuilding humanity in the promised land. York and Eris finally have a child with Ibis congratulating the couple.
So there you have it. Enjoy the game.
We don't make mistakes. We just have happy accidents.
Thanks a lot! I played through the game once, but didn't find it exciting enough to want to go through 2 more times to get this ending, so it's cool to see how things transpired for anyone patient enough to go all the way to the final ending.
I assume it's a 3 stars save slot, right? I ask because I just launched the game to see how far in the game I am, and it seems I do have a 3 stars save slot, but with the 2 first characters on lvl 1. So I probably just started the game, saved, and forgot it still exists.
But it's funny that after so long since the game was released such a small (or big and important) details are revealed. Thanks for info!
EDIT: Haha, turned out that I probably beat Arioch's ending too, but forgot xD
No problem. I'm glad I was able to help out by reminding you of your save file. I found it a bit boring to play through all of the same dungeons again 3 times until you actually got to the good ending. I like the game but its pretty short and starting again from Lv. 1 each time you play the game is not that fun.
We don't make mistakes. We just have happy accidents.