Headcase is an Achievement in Halo 3: ODST. It is awarded for completing any Campaign level on any difficulty with at least one Skull activated. It is worth 5 Gamerpoints.[1]

It is represented by an olive green circle with a skull in front. The skull has glowing red eyes.


  • It doesn't matter whether you use Gold or Silver Skulls to get this achievement, for example, you could get it by only having the IWHBYD Skull activated.