And now onto mechanics.
Dropping typical big RPG numbers and stats for something different.
I explain things poorly so here are just bullet points:

Plays kinda like Pokemon in that you are the trainer.
You can use items and swap out your team and do other special tactical things.
4 members out at a time and you will be encouraged to swap a lot.
Small Paper Mario-like numbers.
You have no HP but if at any point your party cannot act, you die.
Turn order is you first with everyone else actually having a speed stat.

Physical party members typically have a large vitality pool.
They use vitality to attack. A vitality point has 3 states: Healthy, Injured, and Damaged.
Using skills will move healthy to injured state. Taking damage will turn injured points to damaged ones.
They recover a bit of vitality at the start of their next turn.
If vitality hits 0 they are incapacitated and must be revived with an item or skill.

Supernatural party members can take several actions per turn and consume spirit to do so.
Taking damage also consumes spirit.
If spirit hits 0 they are incapacitated and must slowly recharge to full with no other method of recovery.

Holy party members also must balance their resource of Faith.
They will have active skills that typically do a defensive action to do so.
If faith hits 0 they will go into a special state depending on the character, essentially a berserking mode and will not carry out your commands.
A faithless character is considering incapacitated and cannot be swapped out. Talking them through it is the only way to recover them.
Father Gregorio is sleepy. Nicholas is furious. Sister Helen is fearful.

There will be characters who have different elements in their skill kits. Basil has supernatural attacks, though some characters like Ophelia are almost pure in their element.
Phys > Holy > SN > Phys

Roughly the same applies for enemies:
Physical are expected to be tanky
Supernatural can unleash multiple actions
and Holy have death effects