Hai to Gensou no Grimgar

Why are we doing this...? When Haruhiro came to, he was in the darkness. Not knowing why was he here, or where "here" even was. With him were others who also remembered little more than their own names. What they found when they came out of the underground was a world that was "just like a game." In order to survive, Haruhiro forms a party with others in the same situation as him, learns Skills, and takes his first steps forward into the world of Grimgar as a Trainee Volunteer Soldier. Not knowing what awaits him... This is a tale of adventure born from the ashes. (Source: J-Novel Club)