Hidden subtitle in Halo 2
From Halopedia, the Halo wiki
In the beginning video sequence of The Arbiter, just before Rtas 'Vadumee (Half-Jaw) says "And continue our march to glorious salvation!," another subtitle will appear for a split second. Right after the Elites say "We will grind them into dust" the subtitle will say "and wipe them as excrement from our boot!"
Some think the developers took that particular line out because Elites don't actually wear boots.
(*Note: You must have the subtitles in the options menu set to the on position).