its a skull or glitch who knows?

okay u know the place where there it is like a city, well if u can get on the light on the
wall, then u jump and when ur in mid air u press the toggal button, then once ur up there
u turn to ur left go down the hall pick up the skull, ur screen is clear and u can see
everything around u.

i now how go to youtube put in halo2 invincibility walk through by thezmachine12 thats me
:) seriously it works check it out