From the introduction:
The smell of rubber from your suffocating gas mask, border between you and poisonous gas. Clouds of smoke, field of mud, deadly barrage fire, borders between you and enemy. Lines of trenches, borders between your ground and their territory. Bullets flying around you, every inch between you and them is this little, and at the same time endless border between life and death, return to family and death in cold mud. And there are you, human being in this never-ending war. But how much humanity do you have left, in this senseless killing? How much are you willing to sacrifice to live? What is the border between human being and empty shell?
While playing this game, you will find out. Great War will make you.