halo 3 has 13 hidden skulls across the campaign, and one of them changes nothing except what characters say.
The IWHBYD skull, located on The Covenant, makes rare diaolgue much more common. Grunts get chatty, Marines say weird things. Its purely for fun.
grunt Birthday Party is another fun one: headshots on Grunts make confetti and a cheering sound. combine them for maximum chaos in a solo or co-op campaign run. what am i doing wrong??