Také-the main character, is a skilled martial artist. His grandmother trained him in different fighting styles. 

Spectre- Spectre is the power system. Similar to magic, Spectre is the power of ones life energy converted into supernatural forces. Its used in different ways such as, flight, elemental manipulation, visionary, destructive, influential, conjuring, material manipulation, summoning, possession. 

Like explained, Spectre doesn't just revolve around destructive power or force. It can be of mental(psychological), defense, and creational and scientifically use as well.