What is the FINAL FANTASY BRAVE EXVIUS game, how does it work?

According to the introduction of SQUARE ENIX Co.,Ltd., FINAL FANTASY BRAVE EXVIUS is a Role Playing game on the Android platform. There is currently a 4.0.1 version released on Feb 11, 2020, you can see the details below.

So begins a new tale of crystals....

A tried-and-true, yet brand new RPG！

SQUARE ENIX’s first title aimed at a worldwide audience;
a brand new FINAL FANTASY game available for smartphones!
Play an entirely new RPG made in classic FINAL FANTASY style!

Includes characters
from past FINAL FANTASY titles!

Enjoy this expansive storyline
right on your phone!

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Features

-Simple battle feature with strategy!
Easy and interactive battles! Tap the screen to attack, but combine magic abilities with tactical know-how to overpower your opponents in strategic maneuvers!Plus!
High quality CG animations of your favorite FINAL FANTASY summons!

-Search in the field and complete dungeons!
Move characters through fields and dungeons to search for items, hidden paths, and new routes to your destinations!
Talk to people in towns to receive quests. Complete them to get items, gil, and even rare items!
It's got all the many features of an RPG in an easy portable form!

- Arena PVP battles!
Fight other players and get to the top!
Take your favorite party to war against your rivals and fight for great prizes!

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Story

Visions――
The hopes and dreams of
legendary warriors given life.
 
Lapis――
A world of crystals and the visions that slumber within.

Harnessing the power of the crystals,
mankind prospered, nations flourished.
But just as day gives way to night,
that era of peace proved but a fleeting illusion.
 
Now, as their world stands on the precipice
of ruin, two young knights summon visions
to their side as they strike out on a journey
to chase the shadows.
 
So begins a new tale of crystals,
and the heroes who would save them...

Features/Adjustments:
- New quality of life features.

Bug Fixes:
- Fixed the recurring display issue affecting Shui Yu's SPR parameter in the unit details screen.
- Fixed an issue in which units entering battle in Brave Shift form were losing health in between missions for Story Events.