No.0 Core is a perfect core that consists of 3 important functions. It can promote your potency, attack and defense at the same time! 

Besides its exclusive characteristics, it has some common functions like other cores, such as core socket, core synthesis and so on. Moreover, when the No.0 Core is used to socket gears, its progress can be 5 times of common cores!

How to Get It
When your pilot rank reaches Colonel, you can get into the R & D Center (beside the PK mode button) and open Zero Core Swap interface (You can see this function when your pilot rank reaches Major, but you can't use it until you are a Colonel).

Put in No.1-No.10 cores one each and then click Swap, you will get the No.0 core (Once you put in the cores, you can't take them back).

In order to prevent players from putting valuable cores in the swap interface, cores that are smaller than 4 cells, cores with Ultra light effect and cores with sockets are all not allowed to be put in.