I think it's more than just fighting. To win the war, they also need to bring color back to the world. I don't know exactly what that means, but I'm sure they'll need more than just soldiers and people who can fight. Winning a war takes lots of different kinds of people, after all. You need cooks to feed the soldiers, a tactician to plan the army's strategy, investigators and reporters to keep people informed and sway public opinion in your favor... well, you get the idea, I'm sure. I really believe that everyone who's been brought here has some talent the gods think will be useful.