Halo: Reach skulls

As with Halo 3, Halo: Reach has difficulty-multipliers in the appearance of human skulls. In addition, all of the skulls featured in Halo 3 will be included in Reach.

Cloud
The Cloud skull is a new skull featured in Halo: Reach. When the skull is on, the player's Motion Sensor is disabled, similar to the Fog skull in Halo 3.

Yellow
Revealed in Firefight, Yellow is one of the custom made skulls you can have.