Is this a new halo 2 skull? It's after the first gondola, where there are two turrets. You grenade jump up to that ledge with the alien snipers, then go to the right around the structure and it is lying in a little grassy area. it does't say or do anything, i think.
you don't need to grenade jump up there. i get it everytime I do that level. You can find it on all difficulties, even easy.
