To get the Hayabusa helmet, you need to collect all the skulls from the campaign on normal difficulty or higher. Once you do this, the armor permutations will unlock automatically. * To get the Hayabusa Body, you'll need to unlock 5 Skulls and to get the Hayabusa Shoulders, unlock 9 Skulls. To unlock the Katana Sword Add-on (attaches to back of Body Armor), you’ll need to obtain a Halo 3 gamerscore of 1000.