Skull/Halo: Spartan Assault

Skulls in Halo: Spartan Assault are, as with all skulls before them, game modifiers. They change how the game plays, and make it more difficult. Unlike in Halo 2, Halo 3, and Halo: Combat Evolved Anniversary they are all unlocked from the start, and can be used straight away, much like in Halo: Reach and Halo 4. In Halo Spartan Assault, skulls give multipliers to your score.