Crisis Core: Final Fantasy 7 Reunion’s method of leveling up materia differs from that of the original FF7 and even the remake. Instead of winning fights over and over until you gain enough AP, the system is built around a little bit of chaos. You'll have to wait for the DMW (Digital Mind Wave) system to let your currently equipped materia level up.
Thankfully, there’s a way to game the system and level up your materia in Crisis Core: Final Fantasy 7 Reunion while doing no work. This is a method you can come back to at any point in the game when you have materia that needs a little attention.
This trick was discovered in the original PSP game and is also viable in Crisis Core: Final Fantasy 7 Reunion. You can even do it at the start of the game. However, you should probably wait until you have decent materia that is worth mastering.
In Crisis Core: Final Fantasy 7 Reunion, your materia levels up when the DMW reels allow you to. It constantly spins up results while in battle, and if at least two of the numbers match (1-1-1, 2-2-2, etc.), the Materia in that corresponding slot will level up.
There will be times when you level two or three materia in the same fight, but what if you can master all of your materia in the same fight?
You’ll want to hold off for a few chapters before you do this. In fact, it's a good idea to wait until you become SOLDIER 1st Class, so you have two more materia slots to work with. Another way to make this easier is to have access to the Fairy Ring. The Fairy Ring grants Auto-Regen and is the reward for Mission 7-6-2 (A Recruiter’s Close Call).
Here is exactly what you need to do to make sure you master your materia.
The final Sentry can’t defeat Zack, so you can stop playing Crisis Core: Final Fantasy
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