Hi everybody,
English is not my native language and probably because of this I’m not understanding correctly this rule. I need an help, please. 
To enter Aristea does the character need to spend all the required points at once or does Aristea work in a cumulative way, so the points can have been spent in different sessions, until the required number is reached?
Regards.
For Aristea, you need to spend all the Artha at once.
To be complete, epiphanies are reached through cumulative spending.
To get the aristea effect you need to spend the artha all at once. It’s like the other artha effects but it costs quite a bit more. Remember though that artha spent on aristea counts towards your epiphany total so it does get you a lot closer to a permanent shade shift in a hurry.
Thanks for the answers!