Volume 1: (Short) History + System
Volume 2: (Short) History + System
Volume Three: (Long) Dual Systems + Dual Male Protagonists + Machiavellian Strategy + Historical Background + Realistic Survival + Science Fiction
The introduction is updated from time to time to facilitate everyone's understanding of the volumes.
(Mainly because I didn't know that I couldn't change the label after signing the contract)
(ʘ̥∧ʘ̥))
