This uses the item "Spirit" to enhance the demon.
When you clear Story Quest Chapter 1-7, it will become available.
Converts the demon you possess into "Spirit".
※ The demon used will disappear.
・Enhancements are made to 10 "masses" in 3 "panels".
・There is a "one mass release bonus" in which the ability of the demon increases as you open one mass, and an "all release bonus" that can gain the ability by releasing all the mass.
・The mass of panel 3 can not be released until all the mass of panels 1 and 2 are released.
・ The content of panel mass enhancement differs depending on the demon.
Currently there are only a few demons that can be used in "Spirit Merge", but we plan to add them one by one.