Each character offers a unique attack to use against the enemies making it worth progressing through the game in hopes to unlock new heroes. (gameranx.com)
If you immediately raise your own flag, you'll have a difficult way through the game as you will need to constantly upgrade and win new territory. (psnstores.com)
Maybe you even want to go through the game on a higher difficulty or finish the game without killing a single person? (justpushstart.com)