The problem i have with death game mangas is that they all start by taking away choice. Do this or die. What would be more interesting is, do it or not, but if you do, you get stuff. Tihs would mean the characters' desires is what pushes them forward instead of fear for their life, because that's something they all share. It's good that the super cliche, cutesy evil game manager just used an illusion. Offing half the players is not a test of skill or survival.